A pseudo-trigonometry related to Ptolemy's theorem and the hyperbolic geometry of punctured spheres
1970 ◽
Vol 34
(3)
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pp. 817-825
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2006 ◽
Vol 34
(2)
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pp. 429-467
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2011 ◽
Vol 376
(1)
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pp. 383-384
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Keyword(s):
2014 ◽
Vol 116
(1)
◽
pp. 3-20
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