Kimball, W. S. (1952). Calculus of variations by parallel displacement. Butterworth.
Čikaški stil citiranja (17. izdanje)Kimball, William Scribner. Calculus of Variations by Parallel Displacement. London: Butterworth, 1952.
MLA način citiranja (9. izdanje)Kimball, William Scribner. Calculus of Variations by Parallel Displacement. Butterworth, 1952.
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