Dorothea Jappe (violinist and viola player) and Michael Jappe (gamba player and cellist) emerged from the circle around August Wenzinger and are still closely connected to the Schola Cantorum Basilensis, Basel, Switzerland, in teaching and in concerts. They have been involved with the viola and its music for over twenty-five years and their interests in the artistic, educational and scientific aspects are balanced: The much-called «dialogue between research and practice» not only characterizes the work of the Jappes in principle, but especially the essence of the bibliographies at hand.