Não informado. (1971). NLL Announcement Bulletin. National Lending Library for Science and Technology.
Cita Chicago Style (17a ed.)Não informado. NLL Announcement Bulletin. Boston, Inglaterra: National Lending Library for Science and Technology, 1971.
Cita MLA (8a ed.)Não informado. NLL Announcement Bulletin. National Lending Library for Science and Technology, 1971.
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