Blackwell, Paul (1971), “An alternative proof of a theorem of Erdős and Szekeres”, American Mathematical Monthly, 78 (3): 273–273, doi:10.2307/2317525, JSTOR2317525.
jstor.org
Blackwell, Paul (1971), “An alternative proof of a theorem of Erdős and Szekeres”, American Mathematical Monthly, 78 (3): 273–273, doi:10.2307/2317525, JSTOR2317525.