Courant, R., & Robbins, H. E. j. a. (1941). What is mathematicsn An elementary approach to ideas and methods. Oxford university press.
Lua i Stíl Chicago (17ú heag.)Courant, Rchard, agus Herbert Ellis joint author Robbins. What Is Mathematicsn An Elementary Approach to Ideas and Methods. London, New York: Oxford university press, 1941.
Lua MLA (9ú heag.)Courant, Rchard, agus Herbert Ellis joint author Robbins. What Is Mathematicsn An Elementary Approach to Ideas and Methods. Oxford university press, 1941.
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