Cycles of length 0 modulo k in directed graphs

@article{Alon1989CyclesOL,
  title={Cycles of length 0 modulo k in directed graphs},
  author={Noga Alon and Nathan Linial},
  journal={J. Comb. Theory, Ser. B},
  year={1989},
  volume={47},
  pages={114-119}
}
We show that every digraph D with minimum outdegree 6 and maximum indegree A contains a directed cycle of length O(mod k), provided e[dd+ l](1-l/k) " < 1. In particular, if A < (2 "-e)/e6 then D contains an even cycle. 0 1989 Academic Press, Inc.