János Pach, Rom Pinchasi, Micha Sharir. On the number of directions determined by a three-dimensional points set. Journal of Combinatorial Theory, Series A, 108(1):1-16, 2004. [doi]
@article{PachPS04,
title = {On the number of directions determined by a three-dimensional points set},
author = {János Pach and Rom Pinchasi and Micha Sharir},
year = {2004},
doi = {10.1016/j.jcta.2004.04.010},
url = {http://dx.doi.org/10.1016/j.jcta.2004.04.010},
researchr = {https://researchr.org/publication/PachPS04},
cites = {0},
citedby = {0},
journal = {Journal of Combinatorial Theory, Series A},
volume = {108},
number = {1},
pages = {1-16},
}