In the present situation, the maximal bipartite matchings are matchings in G[Vi [ Vj ] with size
min{ni , n j }; we may denote them by Mi j (1 i, j r ). Assume that i < j , thus ni n j and |Mi j | = ni . Then
G −V(Mi j ) has perfect matchings. Note that G −V(Mi j ) is still a complete multi-partite graph with n −2ni vertices
and the number of vertices in the kth part is