3Hague, Eleanor. "Latin American Music"The Fine Arts Press, Santa Ana, California, 1934. Republished by Blaine Ethridge-Books, Detroit, Michigan, 1982.
4Robert Stevenson"Music in Aztec and Inca Territory"University of California Press,Berkeley and Los Angeles,1976.
5Curt Sachs"The History of Musical Instruments"W. W. Norton and Company. Inc. New York. 1940.
6Karl Gustav Izikowitz"Musical and Other Sound Instruments of American Indians"Gothenbeg:Boktryckeri Ak -tiebolag, 1935.