Columbia University Library MS Or 49,
Kitāb Uṣūl al-handasah wa-al-ḥisāb,
كتاب اصول الهندسة والحساب,
arabic translation of Euclid's Elements by Nasir ad Din at Tusi
copied in the mid- to late-19th century


fol 54, figures IV.9 et IV.10 et variantes en bas de page


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