Organizational commitment at saigontourist travel service company

68 539 0
Organizational commitment at saigontourist travel service company

Đang tải... (xem toàn văn)

Tài liệu hạn chế xem trước, để xem đầy đủ mời bạn chọn Tải xuống

Thông tin tài liệu

MASTER OF BUSINESS ADMINISTRATION INTERNATIONAL PROGRAM  RESEARCH PROJECT (BMBR5103) ORGANIZATIONAL COMMITMENT AT SAIGON TOURIST TRAVEL SERVICE COMPANY STUDENT’S FULL NAME : DOAN THI ANH TO STUDENT ID : CGS00019370 INTAKE : MARCH 2015 ADVISOR’S NAME & TITLE : DR KHAI NGUYEN Ho Chi Minh City, July 2016 ACKNOWLEDGEMENTS Dear Dr Khai, I am great grateful for the valid helps from my supervisor who offers many valid comments about this dissertation I am grateful for employees of SaigonTourist Travel Service Company in Vietnam who offer valid information for me to complete this dissertation I am also grateful for my family members, colleagues, and friends who always give me a motive to complete this dissertation Student - Doan Thi Anh To CONTENTS ABSTRACT CHAPTER ONE: INTRODUCTION 1.1 Introduction of Saigontourist Travel Service Company in Vietnam 1.2 Problem statement 1.3 Research objectives 1.4 Research scope 1.5 Research questions 1.6 Significance of research CHAPTER TWO: LITERATURE REVIEW 10 2.1 Definition of constructs 10 2.1.1 Organizational commitment 10 2.1.2 Job cognition 12 2.1.3 Work-related expectancies 12 2.1.4 Empowerment at work scale 13 2.1.5 Goal and process clarity 13 2.1.6 Perceived person-organization fit 14 2.2 Arguments for the relation amongst the constructs 15 2.2.1 The relation amongst job cognition and organizational commitment 15 2.2.2 The relation amongst work-related expectancies and organizational commitment15 2.2.3 The relation amongst empowerment at work scale and organizational commitment 16 2.2.4 The relation amongst goal and process clarity and organizational commitment 16 2.2.5 The relation amongst perceived person-organization fit and organizational commitment 17 2.3 Hypotheses 18 2.4 Research model 19 CHAPTER THREE: METHODS 20 3.1 Data collection 20 3.1.1 Designing template scale 20 3.1.1.1 Organizational commitment 20 3.1.1.2 Job cognition 21 3.1.1.3 Work-related expectancies 22 3.1.1.4 Empowerment at work scale 23 3.1.1.5 Goal and process clarity 23 3.1.1.6 Perceived person-organization fit 25 3.1.2 Progress of data collection 25 3.2 Data analysis 26 CHAPTER FOUR: RESULTS 28 4.1 Demographic information 28 4.2 Reliability test 29 4.2.1 Conditions of reliability test 29 4.2.2 Cronbach’s Alpha of constructs 30 4.2.2.1 Organizational commitment (OC – Main construct) 30 4.2.2.2 Job cognition 30 4.2.2.3 Work-related expectancies 31 4.2.2.4 Empowerment at work scale 31 4.2.2.5 Goal and process clarity 31 4.2.2.6 Perceived person-organization fit 32 4.3 Statistics information 32 4.3.1 Descriptive statistics 32 4.3.2 Correlation analysis 33 4.4 Hypothesis testing 35 4.4.1 Testing of hypothesis 35 4.4.2 Testing of hypothesis 36 4.4.3 Testing of hypothesis 37 4.4.4 Testing of hypothesis 38 4.4.5 Testing of hypothesis 39 CHAPTER FIVE: CONCLUSIONS 42 5.1 Discussion 42 5.2 Study conclusions 43 5.3 Study limitations 44 5.4 Recommendations 46 REFERENCES 48 APPENDIX 1: QUESTIONNAIRE 54 APPENDIX 2: PRESENTATION 59 TABLE Table 1: Organizational commitment 20 Table 2: Job cognition 21 Table 3: Work-related expectancies 22 Table 4: Empowerment at work scale 23 Table 5: Goal and process clarity 24 Table 6: Perceived person-organization fit 25 Table 7: Timetable for the progress of data collection 26 Table 8: Demographic information of surveyed employees 28 Table 9: Conditions of examining the reliability of items 29 Table 10: Cronbach’s Alpha of Organizational commitment 30 Table 11: Cronbach’s Alpha of Job cognition 30 Table 12: Cronbach’s Alpha of Work-related expectancies 31 Table 13: Cronbach’s Alpha of Empowerment at work scale 31 Table 14: Cronbach’s Alpha of Goal and process clarity 31 Table 15: Cronbach’s Alpha of Perceived person-organization fit 32 Table 16: Descriptive statistics of variables 33 Table 17: Correlation analysis of variables 34 Table 18: Model Summary of Hypothesis 35 Table 19: Coefficients of Hypothesis 36 Table 20: Model Summary of Hypothesis 36 Table 21: Coefficients of Hypothesis 37 Table 22: Model Summary of Hypothesis 37 Table 23: Coefficients of Hypothesis 38 Table 24: Model Summary of Hypothesis 38 Table 25: Coefficients of Hypothesis 39 Table 26: Model Summary of Hypothesis 39 Table 27: Coefficients of Hypothesis 40 Business Research Methods P a g e /62 ABSTRACT The aim of this study is to analyze factors affecting organizational commitment of employees of STSC in Vietnam With the research aim, this research has three main objectives as follows: (1) to research the main theories related to organizational commitment of employees, (2) to analyze whether factors like job cognition, empowerment at work scale, goal and process clarity, perceived person-organization fit and work-related expectancies will have effects on organizational commitment of employees of STSC in Vietnam and (3) to suggest recommendations for managers of STSC in Vietnam to increase its employees’ organizational commitment in the future This research is performed by the quantitative study method and the offline surveys of 500 employees of STSC in Vietnam The valid information of 270 questionnaires is used to gain the study objectives This research used the SPSS software of version 16 to analyze the collected data Hypotheses used in this study consist of six constructs: A dependent construct (organizational commitment) and five independent constructs (job cognition, empowerment at work scale, goal and process clarity, perceived person-organization fit and work-related expectancies) After examining all the five hypotheses through correlation analysis and regression analysis, this research concludes that H1, H2, H3, and H4 are supported while H5 is not supported In other words, job cognition, empowerment at work scale, goal and process clarity, and work-related expectancies have positive effects on organizational commitment of employees in STSC in Vietnam while perceived person-organization fit does not have any effect on organizational commitment of employees in STSC in Vietnam Key words: Job cognition, empowerment at work scale, goal and process clarity, perceived person-organization fit, work-related expectancies and organizational commitment Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e /62 CHAPTER ONE: INTRODUCTION 1.1 Introduction of Saigontourist Travel Service Company in Vietnam Core business Saigontourist Travel Service Company (STSC) in Vietnam is a tourism company that has the headquarters in Vietnam Tourism services of this company include business travel service, travel services combined with conference, meeting, workshop, social program, and event, cruise travel, etc The tourism services of this company have satisfied many customers in Vietnam and international customers This company was established in 1975 This company has had strong relationships with more than 400 tourism companies, and agents from many nations such as Japan, France, Spain, the United States, Germany, China, South of Korea, the United Kingdom, etc and is official member of international tourism associations (JATA, PATA, USTOA and ASTA), Ho Chi Minh City Travel Association and Vietnam Tourism Association (Saigontourist Travel Service Company, 2016a) According to Saigontourist Travel Service Company (2016b), STSC in Vietnam concentrates on various business activities to serve all needs and expectations of its customers and core business activities of this company are as follows: - Inbound travel: Tourism services serve international customers to visit regions, cities and communities of Vietnam - Outbound travel: Tourism services serve international customers and domestic customers to visit regions, cities and communities of nations outside Vietnam like Hong Kong, China, France, Italia, Canada, Belgium, Japan, Australia, Germany, the United States, New Zealand, South Korea, Spain, etc Student: Doan Thi Anh To (ID19370) Business Research Methods - P a g e /62 Domestic travel: Tourism services serve domestic customers to visit regions, cities and communities of Vietnam Development timeline According to Saigontourist Travel Service Company (2016a), there are three main business development period of STSC in Vietnam as follows: From 1975 to 2000 STSC in Vietnam gained many rewards from the Vietnamese government from 1975 to 2000 In 2000, this company was the first tourism company serving more than 100,000 inbound cruise tourists to Vietnam Its customers considered this company as the place for them to gain excellent tourism services From 2001 to 2010 STSC in Vietnam gained the brand reputation through applying the tourism service differentiation strategy from 2001 to 2010 In 2010, this company had more than 50,000 cruise travelers participating trans-Viet tours and received many awards from the Vietnamese government such as High Quality Tourism Service and Innovation Tourism Service From 2011 to now STSC in Vietnam has opened new offices in many cities to serve many customers in domestic market and international markets from 2011 to now This company has received many awards from the Vietnamese government such as Vietnam Golden Star Award and High Quality Tourism Service Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e /62 Organizational structure Source: Adapted from Saigontourist Travel Service Company (2016a) STSC’s vision According to Saigontourist Travel Service Company (2016a), the vision of STSC in Vietnam is to become one of the leading tourism companies in the Vietnamese tourism industry in terms of sustainable business development level, and high profits In order to achieve this vision, this company focuses much on five competitive advantages, that is, (1) technological innovation, (2) positive organizational culture and governance system, (3) communityoriented brand, (4) innovative tourism services and (5) strongly integrated value chain  Technological innovation: STSC in Vietnam is willing to buying modern equipment and using advanced tourism technologies to create convenience for its customers and to increase satisfaction level of its customers Indeed, this company is one of the tourism companies in Vietnam of pioneering application of innovative tourism Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 48 /62 REFERENCES Ambad, S N A and Bahron, A (2012) Psychological empowerment: The influence on organizational commitment among employees in the construction sector The Journal of Global Business Management, 8(2), pp 73-81 Arustei, C C (2013) Employees’ organizational commitment challenges – A hotel industry perspective Management Dynamics in the Knowledge Economy, 1(3), pp 497-519 Bhatnagar, J (2007) Predictors of organizational commitment in India: strategic HR roles, organizational learning capability and psychological empowerment International Journal of Human Resource Management, 18(10), pp 1782-1811 Boglera, R and Somech, A (2004) Influence of teacher empowerment on teachers’ organizational commitment, professional commitment and organizational citizenship behavior in schools Teaching and Teacher Education, 20, pp 277-289 Borghei, R., Jandaghi, G., Matin, H Z and Dastani, N (2010) An examination of the relationship between empowerment and organizational commitment International Journal of Human Sciences, 7(2), pp 1155-1171 Bretz, R D and Judge, T A (1994) Person-organization fit and the theory of work adjustment: Implications for satisfaction, tenure and career success Journal of Vocational Behavior, 44, pp 32-54 Caldwell, D F., Chatman, J A and O’Reilly, C A (1990) Building organizational commitment: A multiform study Journal of Occupational Psychology, 63, pp 245-261 Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 49 /62 Chatman, J (1989) Matching people and organizations: Selection and socialization in public accounting firms Academy of Management Best Paper Proceedings Washington, DC: Academy of Management Chughtai, A A and Zafar, S (2006) Antecedents and consequences of organizational commitment among Pakistani university teachers Applied Human Resource Management Research, 11(1), pp 39-64 Davis J A (1971) Elementary survey analysis Englewood, NJ: Prentice-Hall Eisenberger, R., Fasolo, P M and Davis-LaMastro, V (1990) Effects of perceived organizational support on employee diligence, innovation, and commitment Journal of Applied Psychology, 53, pp 51-59 Edwards, J R (1996) An examination of competing versions of the person-environment fit approach to stress Academy of Management Journal, 39, pp 292-339 Fields, D L (2002) Taking the measure of work: A guide to validated scales for organizational research and diagnosis London: Sage George, D and Mallery, P (2003) SPSS for Windows step by step: A simple guide and reference, 4th edition Boston: Allyn & Bacon Kirkman, B L and Rosen, B (1999) Beyond self-management: The antecedents and consequences of team empowerment Academy of Management Journal, 42, pp 58-74 Kraimer, M L., Seibert, S E and Liden, R C (1999) Psychological empowerment as a multidimensional construct: A test of construct validity Educational and Psychological Measurement, 59, pp 127–142 Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 50 /62 Kristof, A L (1996) Person-organization fit: An integrative review of its conceptualizations, measurement and implications Personal Psychology, 49(1), pp 1-49 Lee, K and Allen, N J (2002) Organizational citizenship behavior and workplace deviance: The role of affect and cognitions Journal of Applied Psychology, 87(1), pp 131-142 Luthans, F (2005) Organizational behavior, 10th edition New York: McGraw-Hill Meyer, J P., and Allen, N J (1991) A three-component conceptualization of organizational commitment Human Resource Management Review, 1(1), pp 61-89 Meyer, J P and Allen, N J (2007) A three-component conceptualization of organizational commitment: Some methodological considerations Human Resource Management Review, 1, pp 61-98 Moorman, R H., Niehoff, B P and Organ, D W (1993) Treating employees fairly and organizational citizenship behavior: Sorting the effects of job satisfaction, organizational commitment and procedural justice Employee Responsibilities and Rights Journal, 6(3), pp 209-225 Mowday, R., Porter, L., and Steers, R (2006) Employee organization linkages New York: Academic Press Mowday, R T., Steers, R M and Porter, L W (1979) The measurement of organizational commitment Journal of Vocational Behavior, 14, pp 223-247 Organ, D W and Konovsky, M (1989) Cognitive vs affective determinants of organizational citizenship behavior Journal of Applied Psychology, 74, pp 157-164 Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 51 /62 O’Reilly, C and Chatman, J (1986) Organizational commitment and psychological attachment: The effects of compliance, identification and internalization on pro-social behavior Journal of Applied Psychology, 71(3), pp 492-499 O’Reilly, C A., Chatman, J and Caldwell, D F (1991) People and organizational culture: A profile comparison approach to assessing person-organization fit Academy of Management Journal, 34(3), pp 487-516 Perry, J L., Debra, M and Paarl, B L (2006) Motivating employees in a new governance era: The performance paradigm revisited Public Administration Review, 66(4), pp 505-514 Poorkyani, M., Abayi, N H and Zareie, F (2015) An investigation on the relationship between psychological empowerment and organizational commitment (A case study of the employees of public organizations in Kerman) International Journal of Scientific Management and Development, 3(1), pp 757-766 Raub, S., and Robert, C (2012) Empowerment, organizational commitment, and voice behavior in the hospitality industry evidence from a multinational sample Cornell Hospitality Quarterly, 54(2), pp 136-148 Rehman, K., Rehman, Z U., Saif, N., Khan, A S., Nawaz, A and Rehman, S U (2013) Impacts of job satisfaction on organizational commitment: A theoretical model of academicians in HEI of developing countries like Pakistan International Journal of Academic Research in Accounting, Finance and Management Sciences, 3(1), pp 80-89 Saigontourist Travel Service Company (2016a) About us: History [Online] Available from http://www.saigontourist.net/aboutus.htm (Accessed 06 July, 2016) Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 52 /62 Saigontourist Travel Service Company (2016b) About us: Core business [Online] Available from http://www.saigontourist.net/aboutus-core.htm (Accessed 06 July, 2016) Sawyer, J E (1992) Goal and process clarity specification of multiple constructs of role ambiguity and a structural equation model of their antecedents and consequences The Journal of Applied Psychology, 77, pp 130-142 Spreitzer, G M (1995) Psychological empowerment in the work place: Dimensions, measurement, and validation Academy of Management Journal, 38(5), pp 1442-1465 Thomas, K W and Velthouse, B A (1990) Cognitive elements of empowerment: An “interpretive” model of intrinsic task motivation Academy of Management Review, 15, pp 666-681 Vancouver, J B and Schmitt, N W (1991) An exploratory examination of personorganization fit: Organizational goal congruence Personnel Psychology, 44(2), pp 333-352 Williams, L J and Anderson, S E (1991) Job satisfaction and organizational commitment as predictors of organizational citizenship and in-role behaviors Journal of Management, 17(3), pp 601-617 Wong, A and Sohal, A (2002) An examination of the relationship between trust, commitment and relationship quality International Journal of Retail and Distribution Management, 30(1), pp 34-50 Yuksel, M (2007) Corporate and organizational citizenship: A case from Turkey The Business Review, 8(2), pp 258-266 Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 53 /62 Zahedi, S, Boudlaee, H., Satarinasab, R., Koushki, J., Alireza A (2009) Analysis of the relationship between psychological empowerment and organizational Professional Journal of Parks and Growth Centers, 24, pp 59-69 Student: Doan Thi Anh To (ID19370) commitment Business Research Methods P a g e 54 /62 APPENDIX 1: QUESTIONNAIRE Dear Mr / Ms, My name is Doan Thi Anh To I am a student of MBA Collaboration Program at Open University Malaysia and Ho Chi Minh City University of Technology I am conducting the research for my thesis My research thesis is about: Organizational Commitment at Saigontourist Travel Service Company (STSC) in Vietnam I would like to look for your help by answering the following questionnaire All of your information will be strictly confidentially kept and be solely used for the purpose of my studying Your value time and feedback are extremely useful and meaningful to my fulfillment of my graduation thesis Thank you very much for your very kindly response to this questionnaire It is highly appreciated If you need any information related to this questionnaire, would you please call me at my mobile number 84.908.354.025 or contact with me through my email at anhto2000@yahoo.com Thank you very much! Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 55 /62 Part I: Organizational commitment and factors impacting on organization commitment Please indicate the degree of your evaluation with each statement by circling one of the five scales: Strongly disagree Disagree Neutral Agree Strongly agree No Statement 5 5 5 5 Organizational commitment Your are willing to have the high effort to help the company be successful Your talk up the company to friends as a good company to work for You accept almost kinds of assignment of job to keep working for the company You find that values of the company and your value are very similar You feel proud to tell other people that you are a part of the company The company has the high ability to inspire the best in you in the job conduction approach You are very glad that you select the company to work for over other companies you were considering Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 56 /62 at the time you participated in You care about the fate of the company For you, the company is the best place for you to work Job cognition 10 You have the chance for working alone 11 You have the chance for performing various things 12 Your manager understands employees 13 Your manager makes competent decision 14 Your job is stable job 15 You have chance for using abilities to conduct your 5 job 16 Your company clearly informs about corporate policy 17 There is a suitability between payment and the amount of work 18 You have chance for career development 19 Your company has good work conditions Work-related expectancies 20 You gain payment increase in the case of high work performance 21 You receive fair treatment of your supervisor 22 You gain recognition of your supervisors in the case of high work performance 23 Your supervisor pays attention to opinions of the best employees 24 You have the influence on decision-making of your managers 25 You have job security in the case of high work Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 57 /62 performance 26 Your gain work delegation of your supervisors 27 You gain career development in the case of high work performance Empowerment at work scale 28 There is the importance of your job to you 29 There is the meaningfulness of your job to you 30 You have the confidence about the ability to conduct 5 5 job 31 You have job autonomy 32 You have chance for freedom and independence in how to conduct job 33 You have the influence of employee on what occurs in the work department 34 You have the control over what occurs in the work department Goal and process clarity 35 There is the clarity of your responsibilities and duties 36 There is the clarity of objectives and goals of your job 37 There is the clarity of the relation between the 5 5 common objectives of work unit and your work performance 38 There is the clarity of expectations of the company for your work results 39 The aspects of your work of leading to positive evaluations are clear 40 The way to divide the time amongst tasks required by Student: Doan Thi Anh To (ID19370) Business Research Methods P a g e 58 /62 your job is clear 41 The way to determine the suitable procedures for each task of your job is clear 42 There is the correction of procedures of your job 43 The way to schedule your daily work is clear 44 You have the capability to know the best way to 5 5 conduct your job-related tasks Perceived person-organization fit 45 There is the fit between your values and values of the organization 46 There is the fit between your values and other employees in the company 47 The company satisfies your needs and expectations Part II: Personal Information Gender  Male  Female Age  Under 24 years old  From 24 to 36 years old  From 37 to 45 years old  Above 45 years old Academic degree  High school  Colleges Degree  Master Degree  Doctoral Degree  Bachelor Degree Working seniority  Under years  From to years  From to years  Above years You have successfully done the questionnaire Thank you very much! Student: Doan Thi Anh To (ID19370) Business Research Methods APPENDIX 2: PRESENTATION Student: Doan Thi Anh To (ID19370) P a g e 59 /62 Business Research Methods Student: Doan Thi Anh To (ID19370) P a g e 60 /62 Business Research Methods Student: Doan Thi Anh To (ID19370) P a g e 61 /62 Business Research Methods Student: Doan Thi Anh To (ID19370) P a g e 62 /62 [...]... relation amongst perceived person-organization fit and organizational commitment The suitability of an organization and its organizational members can happen when its organizational members match with each other in a work environment, when its organizational members’ features supplement something to the work environment that is missing, when the organization satisfies personal demands and expectations... 10 /62 CHAPTER TWO: LITERATURE REVIEW 2.1 Definition of constructs 2.1.1 Organizational commitment Organizational commitment is considered as the responsibility feeling which employees have toward their organization’s mission In organizational psychology, organizational commitment is psychology attachment of employees to their company and it predicts work efficacy, organizational citizenship behavior... employees’ organizational commitment in STSC in Vietnam H3: Empowerment at work scale has a positive relationship with employees’ organizational commitment in STSC in Vietnam H4: Goal and process clarity has a positive relationship with employees’ organizational commitment in STSC in Vietnam H5: Perceived person-organization fit has a positive relationship with employees’ organizational commitment. .. continuous work commitment Employees who have the great degree of normative commitment feel that they should stay with their company so that they can have high contributions to their company to “repay their company s debt” Indeed, they have received many benefits such as training and other benefits and then they express their great gratitude to their company through high organizational commitment (Meyer... organization, these attributes can be organizational culture, goals, values, climate and norms When a company satisfied personal expectations and needs of its organizational members, its organizational members will meet its demands and expectations (Kristof, 1996; Chughtai and Zafar, 2006) Based on the model of Bretz and Judge (1994), perceived person-organization fit is measured through three items, that... Many researchers have created different scales to evaluate organizational commitment In particular, three-factor commitment model of Meyer and Allen indicates three various factors related to organization commitment of employees The first factor is affective commitment and it is positively emotional attachment of employees to their company and they desire to be parts of their company because they want... related to organizational commitment of employees - To analyze whether factors like job cognition, empowerment at work scale, goal and process clarity, perceived person-organization fit and work-related expectancies will have effects on organizational commitment of employees of STSC in Vietnam - To suggest recommendations for managers of STSC in Vietnam to increase its employees’ organizational commitment. .. to the three-factor commitment model of Meyer and Allen The psychologists argue that organizational commitment is the psychology bond that makes employees attach to their company and the bond nature consists of three forms, internalization, identification and compliance (O’Reilly and Chatman, 1986) Internalization happens when the effect is accepted since the included beliefs and attitudes are congruent... industry and then, this company focuses much on research and development (R&D) activities to create a range of innovative tourism services This company has had a range of innovative tourism services that meet needs and expectations of its customers and this is the way for this company to retain its current customers and to attract attention of its potential customers  Strongly integrated value chain: STSC... jobs in other companies rather than stay with their company Therefore, work-related expectancies have a positive relation job commitment of employees (Rehman et al., 2013) 2.2.3 The relation amongst empowerment at work scale and organizational commitment According to Thomas and Velthouse (1990), employee empowerment is very crucial for manages to increase their organizational commitment In particular, ... business Saigontourist Travel Service Company (STSC) in Vietnam is a tourism company that has the headquarters in Vietnam Tourism services of this company include business travel service, travel services... City Travel Association and Vietnam Tourism Association (Saigontourist Travel Service Company, 2016a) According to Saigontourist Travel Service Company (2016b), STSC in Vietnam concentrates on... relation amongst job cognition and organizational commitment 15 2.2.2 The relation amongst work-related expectancies and organizational commitment1 5 2.2.3 The relation amongst empowerment at

Ngày đăng: 07/12/2016, 11:31

Từ khóa liên quan

Tài liệu cùng người dùng

  • Đang cập nhật ...

Tài liệu liên quan