Ayres, F. J. (1954). Schaum's outline of theory and problems of plane and spherical trigonometry. McGraw Hill.
Trích dẫn kiểu ChicagoAyres, Frank Junior. Schaum's Outline of Theory and Problems of Plane and Spherical Trigonometry. New York: McGraw Hill, 1954.
Trích dẫn MLAAyres, Frank Junior. Schaum's Outline of Theory and Problems of Plane and Spherical Trigonometry. McGraw Hill, 1954.
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