Plantholt, Michael J., and Shailesh K. Tipnis. “Vertex-Oriented Hamilton Cycles in Directed Graphs”. The Electronic Journal of Combinatorics 16, no. 1 (September 18, 2009): #R115. Accessed April 30, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v16i1r115.