O'Connor, John J.; Robertson, Edmund F. (2000). "The Indian Sulbasutras". MacTutor History of Mathematics archive. St Andrews University. Archived from the original on 7 April 2016. Retrieved 13 January 2022.
O'Connor, John J.; Robertson, Edmund F. (2000). "The Indian Sulbasutras". MacTutor History of Mathematics archive. St Andrews University. Archived from the original on 7 April 2016. Retrieved 13 January 2022.