Ayres, F. (1952). Schaum's outline of theory and problems of differential equations. Schaum Pub.
Chicago-viite (17. p.)Ayres, Frank. Schaum's Outline of Theory and Problems of Differential Equations. New York: Schaum Pub, 1952.
MLA-viite (9. p.)Ayres, Frank. Schaum's Outline of Theory and Problems of Differential Equations. Schaum Pub, 1952.
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