Gaya APA

Wan, F, Y., Swanson, C, P. (NULL). Introduction to the calculus of variations and its applications . New: New York: Chapman & Hall; 1995.

Gaya MLA

Wan, Frederick, Y.M.., Swanson, Carl, P.. "Introduction to the calculus of variations and its applications". New: New York: Chapman & Hall; 1995, NULL. Text.