Columbia University Library MS Or 282,
Persian translation by Qotb al-Din Chirazi
of Nasīr al-Dīn al-Tūsī’s edition of Euclid’s Elements,
dated beginning of Shaʻbān in 780 A.H. (December 1378 CE),


fol 68v, figures XIII.11 et 13 en bas de page


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