Erskine, J. (1944). A musical companion: A guide to the understanding and enjoyment of music. Tudor Pub. Co..
Chicago-viite (17. p.)Erskine, John. A Musical Companion: A Guide to the Understanding and Enjoyment of Music. N.Y.: Tudor Pub. Co., 1944.
MLA-viite (8. p.)Erskine, John. A Musical Companion: A Guide to the Understanding and Enjoyment of Music. Tudor Pub. Co., 1944.
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