G. N. Zholtkevich, B. V. Novikov, and L. Y. Polyakova, “Decomposition of Directed Graphs and the Turán Problem”, Ukr. Mat. Zhurn., vol. 66, no. 7, pp. 958–969, Jul. 2014, Accessed: Dec. 14, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/2191