Rafael Jakimczuk
      A generalization of the inclusion-exclusion principle
      International Mathematical Forum, Vol. 9, 2014, no. 34, 1669-1672
      http://dx.doi.org/10.12988/imf.2014.49165
Copyright © 2014 Rafael Jakimczuk. This article is distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.