APA

Troutman J. L., Hrusa W., . (1983). Variational calculus with elementary convexity. New York [u.a.]: Springer.

Chicago

Troutman John L, Hrusa William, . 1983. Variational calculus with elementary convexity. New York [u.a.]: Springer.

Harvard

Troutman J. L., Hrusa W., . (1983). Variational calculus with elementary convexity. New York [u.a.]: Springer.

MLA

Troutman John L, Hrusa William, . Variational calculus with elementary convexity. New York [u.a.]: Springer. 1983.