The first textbook of calculus: Yuktibhāṣā (Q935689)

An ample presentation of the historical background, the content -- which includes several theorems commonly attributed to 17th century European mathematicians (Gregory, Leibniz, Newton) -- and the reason why it ought to be considered the first calculus textbook, of the \textit{Yuktibhāṣā}, a work on mathematics and astronomy, written around 1550--1560 CE not in Sanskrit verse but in Malayalam prose (the language of Kerala).