MLA

Ulugh Beg, 1394-1449. Zīj-i Gūrgānī : manuscript. 1779 or 1780.. https://collections.library.yale.edu/catalog/10841803.

APA, 6th edition

Ulugh Beg, 1394-1449. (1779 or 1780.)[Zīj-i Gūrgānī : manuscript]. https://collections.library.yale.edu/catalog/10841803.