Techniques of Variational Analysis
Borwein is an authority in the area of mathematical optimization, and his book makes an important contribution to variational analysis
Provides a good introduction to the topic
Calculus of variations
Citation for published book
Borwein, Jonathan, and Qiji J. Zhu. Techniques in Variational Analysis. New York, NY: Springer, 2005.
Borwein, Jonathan M. and Zhu, Qiji, "Techniques of Variational Analysis" (2005). All Books and Monographs by WMU Authors. 334.