Glenn, M. 1., Leavitt, H. S. 1., Rebmann, V. L. F. 1., Baker, E. L. 1., & Kirby, C. V. 1. (1943). Blending voices (Enlarged edition.). Boston: Ginn and Company.

Glenn, Mabelle 1881-1969, Helen Sewall. 1880-1958 Leavitt, Victor Ludwig Fidelis 1880-1974 Rebmann, Earl L. 1888- Baker, and Clarence Valentine 1875-1947 Kirby. Blending Voices. Enlarged edition. Boston: Ginn and Company, 1943.

Glenn, Mabelle 1881-1969, et al. Blending Voices. Enlarged edition. Boston: Ginn and Company, 1943.