Sawyer, W. W. (1943). Mathematician's delight. Penguin Books Ltd.
Lua i Stíl Chicago (17ú heag.)Sawyer, Walter W. Mathematician's Delight. England: Penguin Books Ltd, 1943.
Lua MLA (9ú heag.)Sawyer, Walter W. Mathematician's Delight. Penguin Books Ltd, 1943.
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