Alex Bean Sabina Siddiqi Anila Chowdhury Billy Whited Orit Shaer Robert J. K. Jacob Marble track audio manipulator (MTAM): a tangible user interface for audio composition. 27-30 2008 Tangible and Embedded Interaction http://doi.acm.org/10.1145/1347390.1347398 conf/tei/2008 db/conf/tei/tei2008.html#BeanSCWSJ08