(1)
Markosyan, S. E.; Khachaturyan, A. H. OPTIMAL LEVEL PLACEMENT OF THE TRANSITIVE ORIENTED AND BIPARTITE ORIENTED GRAPHS BY HEIGHT. Proc. YSU A: Phys. Math. Sci. 2009, 43 (2 (219), 43-49. https://doi.org/10.46991/PYSUA.2009.43.2.043.