(1997). Ulrich's international periodicals directory 1997: Including irregular serials & annuals (35th edition.). Bowker.
Chicago-viite (17. p.)Ulrich's International Periodicals Directory 1997: Including Irregular Serials & Annuals. 35th edition. New York: Bowker, 1997.
MLA-viite (9. p.)Ulrich's International Periodicals Directory 1997: Including Irregular Serials & Annuals. 35th edition. Bowker, 1997.
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