Não informado. (1968). World meetings outside United States and Canada. Technical Meetings Information Service.
Chicago-viite (17. p.)Não informado. World Meetings Outside United States and Canada. Newton Centre, Mass: Technical Meetings Information Service, 1968.
MLA-viite (8. p.)Não informado. World Meetings Outside United States and Canada. Technical Meetings Information Service, 1968.
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