Todhunter, Isaac. “LVI. On a Problem in the Calculus of Variations”. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, vol. 42, no. 282, pp. 440-1, https://doi.org/10.1080/14786447108640602.
Todhunter, I. (n.d.). LVI. On a problem in the calculus of variations. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, 42(282), 440-441. https://doi.org/10.1080/14786447108640602
Todhunter I. LVI. On a problem in the calculus of variations. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 42(282):440-1.