Abstract
We prove that Euler’s ratio-sum formula is valid in a projective-metric space if and only if it is either elliptic, hyperbolic, or Minkowskian.
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This research was supported by NFSR of Hungary (NKFIH) under grant numbers K 116451 and KH_18 129630.
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Kurusa, Á., Kozma, J. Euler’s ratio-sum formula in projective-metric spaces. Beitr Algebra Geom 60, 379–390 (2019). https://doi.org/10.1007/s13366-018-0422-6
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DOI: https://doi.org/10.1007/s13366-018-0422-6