APA Edition Citation

Gelfand, I. M., & Fomin, S. V. (1963). Calculus of variations.

Chicago Edition Citation

Gelfand, I M., and S V. Fomin. Calculus of Variations. Prentice-Hall Inc., Englewood Cliffs, New Jersey, 1963.

MLA Edition Citation

Gelfand, I M., and S V. Fomin. Calculus of Variations. 1963.