An Introduction to the Calculus of Variations and several others as well

and several others as well as their inverses

In Wake-Robin: A Collection of Essays About the Birds

In one van Gogh admits: "I can't disguise from you the fact that I like the country

Diophantine problems

and drapery and the sense of balance in each pose are the result of Mucha's instinct for composition

An Introduction to the Calculus of Variations and several others as wellAn understanding of variational methods, the source of such fundamental theorems as the principle of least action and its various generalizations, is essential to the study of mathematical physics and applied mathematics. In this highly regarded text, aimed at advanced undergraduate and graduate students in mathematics, the author develops the calculus of variations both for its own intrinsic interest and because of its wide and powerful applications