“Original Letters from James Gregorie, Professor of Mathematics in the University of St Andrews, to the Reverend Colin Campbell, Minister of Ardchattan, Argyleshire”, arch-scot, vol. 3, pp. 275–284, Nov. 1832, Accessed: Dec. 08, 2025. [Online]. Available: https://journals.socantscot.org/index.php/arch-scot/article/view/231