“…Besides K n * m , complete multipartite graphs with one vertex class of different size were studied. Independently and simultaneously with the preprint version of [12], the 4-cycle systems over K n * m were considered with additional requirements of symmetry in the unpublished manuscript by Cho, Ferrara, Gould, and Schmitt [13] and, later, in the closely related publication by Kim, Cho, and Cho [14].…”