@article{CM_1935__2__463_0, author = {Erd\"os, P\'al and Szekeres, G.}, title = {A combinatorial problem in geometry}, journal = {Compositio Mathematica}, publisher = {Johnson Reprint Corporation}, volume = {2}, year = {1935}, pages = {463-470}, zbl = {0012.27010}, language = {en}, url = {http://www.numdam.org/item/CM_1935__2__463_0} }