APA (7th ed.) Citation

Elsgolc, L. E. (1961). Calculus of variations. Addison-Wesley.

Chicago Style (17th ed.) Citation

Elsgolc, L. E. Calculus of Variations. Reading: Addison-Wesley, 1961.

MLA (9th ed.) Citation

Elsgolc, L. E. Calculus of Variations. Addison-Wesley, 1961.