  The hypercube Qn of dimension n is one of the most versatile and powerful
interconnection networks. The n-dimensional folded cube denoted as FQn, a
variation of the hypercube possesses some embeddable properties that the
hypercube does not possess. Dong and Wang(In Theor. Comput. Sci.771(2019)93-98)
conjectured that "A subset Em of edges of FQn is a perfect matching if and only
if FQn - Em is isomorphic to Qn". In this paper, we disprove this conjecture by
providing some perfect matchings removal of which from FQn do not give a graph
isomorphic to Qn.
