@inproceedings{anders1987an, title={An extended Euler-Poincaré theorem}, author={Anders Björner, and Gil Kalai}, url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203311668120425}, booktitle={Acta Mathematica}, volume={161}, number={1}, pages={279-303}, year={1987}, }