Hiroshi Narushima. Principle of inclusion-exclusion on partially ordered sets. Discrete Mathematics, 42(2-3):243-250, 1982. [doi]
@article{Narushima82,
title = {Principle of inclusion-exclusion on partially ordered sets},
author = {Hiroshi Narushima},
year = {1982},
doi = {10.1016/0012-365X(82)90221-7},
url = {http://dx.doi.org/10.1016/0012-365X(82)90221-7},
researchr = {https://researchr.org/publication/Narushima82},
cites = {0},
citedby = {0},
journal = {Discrete Mathematics},
volume = {42},
number = {2-3},
pages = {243-250},
}