Friis-Hansen, J. B. (1972). Sixty exercises in the registration of gramophone records. Danmarks Bibliotesskole.
Cita Chicago Style (17a ed.)Friis-Hansen, J. B. Sixty Exercises in the Registration of Gramophone Records. Copenhagen: Danmarks Bibliotesskole, 1972.
Cita MLA (9a ed.)Friis-Hansen, J. B. Sixty Exercises in the Registration of Gramophone Records. Danmarks Bibliotesskole, 1972.
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