Productivity of Telemedical Services: A State of the Art Analysis of Input and Output Factors Peters, Christoph Peters Christoph Drees, Alexander Drees Alexander Leppert, Florian Leppert Florian Menschner, Philipp Menschner Philipp Leimeister, Jan Marco Leimeister Jan Marco Möller, Klaus Möller Klaus Greiner, Wolfgang Greiner Wolfgang Fraunhofer-Verl. 2011 application/pdf