Prithudaka
O'Connor, John J.; Robertson, Edmund F., “Prthudakasvami”, MacTutor History of Mathematics archive, University of St Andrews, https://mathshistory.st-andrews.ac.uk/Biographies/Prthudakasvami/ .
Pottage, John (1974), “The mensuration of quadrilaterals and the generation of Pythagorean triads: a mathematical, heuristical and historical study with special reference to Brahmagupta's rules”, Archive for History of Exact Sciences 12 (4): 299–354, doi:10.1007/BF01307176, MR0465678
↑ Pottage 1974, See in particular the footnote on p. 313..