“…It is a useful tool in describing the homology groups of the Steenrod algebra, Tor A k,k+d (F 2 , F 2 ). This transfer was studied by Boardman [2], Bruner, Ha and Hung [3], Ha [5], Hung [9], Chon and Ha [4,10,11], Minami [12], Nam [7], Hung and Quynh [6], the present author [13] and others.…”