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 55v, figure IV.12 et variante

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 55v, figure IV.12 et variante

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