... Insertion of a Contra - Continuous Function*Majid MirmiranDepartment of Mathematics, University of IsfahanIsfahan 81746-73441, IranReceived February 22, 2004Revised October 20, 2005Abstract. ... uρximplies uρyfor any u andv in S.Definition 2.3. A binary relation ρ in the power set P (X) of a top ologicalspace X is calle d a strong binary relation in P (X) in case ρ satisfies each of thefollowing ... If A iρBj for any i ∈{1, ,m} and for any j ∈{1, ,n}, then thereexists a set C in P (X) such that A iρCand CρBj for any i ∈{1, ,m}and any j ∈{1, ,n}.2) If A ⊆ B,thenA ¯ρB.3) If A B,thenAΛ⊆...