An Elementary Proof of Marden's Theorem

@article{Kalman2008AnEP,
  title={An Elementary Proof of Marden's Theorem},
  author={Dan Kalman},
  journal={The American Mathematical Monthly},
  year={2008},
  volume={115},
  pages={330 - 338}
}
  • D. Kalman
  • Published 1 April 2008
  • Mathematics
  • The American Mathematical Monthly
I call this Marden’s Theorem because I first read it in M. Marden’s wonderful book [6]. But this material appeared previously in Marden’s earlier paper [5]. In both sources Marden attributes the theorem to Siebeck, citing a paper from 1864 [8]. Indeed, Marden reports appearances of various versions of the theorem in nine papers spanning the period from 1864 to 1928. Of particular interest in what follows below is an 1892 paper by Maxime Bocher [1]. In his presentation Marden states the theorem… 

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