@article{VUU_2015_25_4_a0,
     author = {Kh. Sh. Al' Dzhabri and V. I. Rodionov},
     title = {The graph of acyclic digraphs},
     journal = {Vestnik Udmurtskogo universiteta. Matematika, mehanika, kompʹ\^uternye nauki},
     pages = {441--452},
     year = {2015},
     volume = {25},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VUU_2015_25_4_a0/}
}