... 36, (20 03), 915-938. [ 26 ] Nguyễn Thành Long, Asymptotic expansion of the solution for nonlinear wave equation with the mixed homogeneous conditions , Nonlinear Anal. 45 (20 01), 26 1 -27 2. ... conditions , J. Math. Anal. Appl. 27 4, No.1 (20 02) , 1 02- 123 . [28 ] Nguyễn Thành Long, On the nonlinear wave equation ,,( 2 utBu tt − ),,,,,,,(), 22 222 txtxxxtx uuuuuutxfuuu = associated with the ... Math., 38 (20 05), No .2, 365 -3 86. [33] Nguyễn Thành Long, Lê Văn Út, Nguyễn Thò Thảo Trúc, On a shock problem involving a linear viscoelastic bar , Nonlinear Anal., 32 (20 05), 198 -22 4. [34]...