Edward A. Bender, Robert W. Robinson. The asymptotic number of acyclic digraphs, II. Journal of Combinatorial Theory, Series A, 44(3):363-369, 1988. [doi]
@article{BenderR88,
title = {The asymptotic number of acyclic digraphs, II},
author = {Edward A. Bender and Robert W. Robinson},
year = {1988},
doi = {10.1016/0095-8956(88)90044-5},
url = {http://dx.doi.org/10.1016/0095-8956(88)90044-5},
researchr = {https://researchr.org/publication/BenderR88},
cites = {0},
citedby = {0},
journal = {Journal of Combinatorial Theory, Series A},
volume = {44},
number = {3},
pages = {363-369},
}