An addendum to the preceding text, al-Risāla al-Shamsīyah fī al-uṣūl al-ḥisābīyah (الرسالة الشمسية في الأصول الحسابية) by Niẓām al-Dīn al-Ḥasan ibn Muḥammad al-Nīsābūrī (نظام الدين الحسن بن محمد النيسابوري; d. 1328 or 1329). The addendum was presumably written in Shīrāz during the late 13th or e...