Frankel, T. (1979). Gravitational curvature: An introduction to Einstein's theory. W.H. Freeman and Company.
Chicago Style aipamenaFrankel, Theodore. Gravitational Curvature: An Introduction to Einstein's Theory. San francisco: W.H. Freeman and Company, 1979.
MLA aipamenaFrankel, Theodore. Gravitational Curvature: An Introduction to Einstein's Theory. W.H. Freeman and Company, 1979.
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