Pappus's theorem and the modular group
Publications Mathématiques de l'IHÉS, Volume 78  (1993), p. 187-206
@article{PMIHES_1993__78__187_0,
author = {Schwartz, Richard Evan},
title = {Pappus's theorem and the modular group},
journal = {Publications Math\'ematiques de l'IH\'ES},
publisher = {Institut des Hautes \'Etudes Scientifiques},
volume = {78},
year = {1993},
pages = {187-206},
zbl = {0806.57004},
language = {en},
url = {http://www.numdam.org/item/PMIHES_1993__78__187_0}
}

Schwartz, Richard Evan. Pappus's theorem and the modular group. Publications Mathématiques de l'IHÉS, Volume 78 (1993) , pp. 187-206. http://www.numdam.org/item/PMIHES_1993__78__187_0/

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