American Library Association & Article 19 (Organization). (1991). Information freedom and censorship: World report 1991. American Library Association.
Dyfyniad Arddull ChicagoAmerican Library Association and Article 19 (Organization). Information Freedom and Censorship: World Report 1991. Chicago: American Library Association, 1991.
Dyfyniad MLAAmerican Library Association and Article 19 (Organization). Information Freedom and Censorship: World Report 1991. American Library Association, 1991.
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