MAXIMAL SUBSETS OF PAIRWISE NON-COMMUTING ELEMENTS OF p-GROUPS OF ORDER LESS THAN p6

Let G be a non-abelian group of order pn, where n  5 in which G is not extra special of order p5. In this paper we determine the maximal size of subsets X of G with the property that xy 6= yx for any x; y in X with x 6= y.