1. Abraham, Ralph. 1967. Foundations of mechanics. New York: W. A. Benjamin, Inc.
2. Arthurs, A.M. 1975. Calculus of variations. London: Routledge & Kegan Paul.
3. Akhiezer, N. I. 1988. The Calculus of Variations. Translated from the Russian edition of 1981 by Michael E. Alferieff. Harwood Academic Publishers. London etc. The author was born in 1901 and the references to the literature are mainly from before 1970. Chapter 4 is titled “Canonical Variables” and deals with Hamilton-Jacobi theory and canonical transformations.
4. Barrow Green, June. 1997. Poincaré and the Three Body Problem. Volume 11 in the series “History of Mathematics”, American and London Mathematical Societies.
5. Bell, Eric T. 1986. Men of Mathematics. Touchstone Press. New York et al. Reprint of the original 1937 edition.