The spectrum for the decomposition of \(\lambda K_v\) into \(3\)-perfect \(9\)-cycles is found for all \(\lambda > 1\). (The case \(\lambda = 1\) was dealt with in an earlier paper by the authors and Lindner.) The necessary conditions for the existence of a suitable decomposition turn out to be sufficient.
Citation
Peter Adams, Elizabeth J.Billington. Lambda-fold \(3\)-perfect \(9\)-cycle systems[J], Ars Combinatoria, Volume 044. 241-262. .