Langner, M. C. (1967). The National Library of Medicine's Services: Initial Observations on Indexing, Interlibrary Loan, and Reference.
Chicago-tyylinen lähdeviittausLangner, Mildred Crowe. The National Library of Medicine's Services: Initial Observations On Indexing, Interlibrary Loan, and Reference. 1967.
MLA-viiteLangner, Mildred Crowe. The National Library of Medicine's Services: Initial Observations On Indexing, Interlibrary Loan, and Reference. 1967.
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