Columbia University Library MS Or 30,
Uṣūl al-handasah wa-al-ḥisāb, Uqlīdis, اصول الهندسة والحساب / اقليدس. Iran?, 1348.
Copy of the Arabic translation of Euclid's Elements by Nasir ad Din at Tusi
p 13, figures I.1 et I.2 avec ses variantes
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