A musician in South Africa has asked for help in locating scores of Czech composer Jan Jakub Simon Ryba's "Missa in B". Does anyone know of a source for the score of this Mass? Ryba's Missa in C, the "Christmas Mass" or "Bohemian Pastoral Mass", is much better known, and readily available, including via CPDL, but my searches have not been able to locate a source for the Missa in B, even commercially. The Worldcat catalog shows that libraries in Chicago and Zurich have copies.