Martin, L. A., & Shaughnessy, T. W. (1967). Progress and problems of Pennsylvania libraries: A resurvey. Pennsylvania State Library.
Chicago-viite (17. p.)Martin, Lowell Arthur, ja Thomas W. Shaughnessy. Progress and Problems of Pennsylvania Libraries: A Resurvey. Harrisburg: Pennsylvania State Library, 1967.
MLA-viite (9. p.)Martin, Lowell Arthur, ja Thomas W. Shaughnessy. Progress and Problems of Pennsylvania Libraries: A Resurvey. Pennsylvania State Library, 1967.
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