APA (7th ed.) Citation

El'sgol'c, L. E. (1961). Calculus of variations. Pergamon Press.

Chicago Style (17th ed.) Citation

El'sgol'c, Lev Ernestovic. Calculus of Variations. Oxford [u.a.]: Pergamon Press, 1961.

MLA (9th ed.) Citation

El'sgol'c, Lev Ernestovic. Calculus of Variations. Pergamon Press, 1961.

Warning: These citations may not always be 100% accurate.