Monatshefte für Mathematik

, Volume 117, Issue 1, pp 63-94

First online:

John disks and extension of maps

  • M. GhamsariAffiliated withDepartment of Mathematics, Christopher Newport University
  • , R. NäkkiAffiliated withJyväskylän yliopisto, Matematiikan laitos
  • , J. VäisaläAffiliated withHelsingin yliopisto, Matematiikan laitos

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We show that a quasisymmetric map between the boundaries of two John disks can be extended to a quasiconformal map of the extended plane. Additional results on John disks are also given.

1991 Mathematics Subject Classification