can also be made by stretching a string with the hand. A string may be tuned down by pulling it above the fingerboard, or tuned up by pressing the part of the string in the pegbox. These techniques may be useful in performance, reducing the ill effects of an out-of-tune string until an opportunity to tune properly. The tuning C–G–D–A is used for the great majority of all viola music. However, other tunings are occasionally employed, both in classical music, where the technique is known as scordatura, and in some folk styles. Mozart, in his Sinfonia Concertante for Violin, Viola and Orchestra in E, wrote the viola part in D major, and specified that the violist raises the strings in pitch by a semitone. He probably intended to give the viola a brighter tone so the rest of the ensemble wouldn't overpower it. Lionel Tertis, in his transcription of the Elgar cello concerto, wrote the slow movement with the C string tuned down to B, enabling the viola to play one passage an octave lower. Organizations and research A renewal of interest in the viola by performers and composers in the twentieth century led to increased research devoted to the instrument. Paul Hindemith and Vadim Borisovsky made an early attempt at an organization, in 1927, with the Violists' World Union. But it was not until 1968, with the creation of the Viola-Forschungsgesellschaft, now the International Viola Society (IVS), that a lasting organization took hold. The IVS now consists of twelve chapters around the world, the largest being the American Viola Society (AVS), which publishes the Journal of the American Viola Society. In addition to the journal, the AVS sponsors the David Dalton Research Competition and the Primrose International Viola Competition. The 1960s also saw the beginning of several research publications devoted to the viola, beginning with Franz Zeyringer's, Literatur für Viola, which has undergone several versions, the most recent being in 1985. In 1980, Maurice Riley produced the first attempt at a comprehensive history of the viola, in his History of the Viola, which was followed with the second volume in 1991. The IVS published the multi-language Viola Yearbook from 1979 to 1994, during which several other national chapters of the IVS published respective newsletters. The Primrose International Viola Archive at Brigham Young University houses the greatest amount of material related to the viola, including scores, recordings, instruments, and archival