APA (7th ed.) Citation

Rektorys, K. (1980). Variational methods in mathematics, science and engineering (2nd edition.). D. Reidel Publishing Company.

Chicago Style (17th ed.) Citation

Rektorys, Karel. Variational Methods in Mathematics, Science and Engineering. 2nd edition. Dordrecht: D. Reidel Publishing Company, 1980.

MLA (8th ed.) Citation

Rektorys, Karel. Variational Methods in Mathematics, Science and Engineering. 2nd edition. D. Reidel Publishing Company, 1980.