球面
1 2 Albert 2016, p. 54.
1 2 3 Woods 1961, p. 266.
↑ Kreyszig 1972, p. 342.
↑ Albert 2016, p. 60.
↑ Steinhaus 1969, p. 223.
↑ Weisstein, Eric W. "Sphere". mathworld.wolfram.com (英語).
↑ Steinhaus 1969, p. 221.
↑ Albert 2016, p. 55.
↑ Albert 2016, p. 57.
1 2 3 4 Woods 1961, p. 267.
↑ Albert 2016, p. 58.
↑ Weisstein, Eric W. "Spheric section". mathworld.wolfram.com (英語).
↑ Hilbert, David; Cohn-Vossen, Stephan (1952). Geometry and the Imagination (2nd ed.). Chelsea. ISBN 0-8284-1087-9
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