APA-ийн эшлэл(7 дахь хэвлэлт)

International Consortium on Research in Science and Mathematics Education [3° : 1991 : Mérida, Yucatán]. (1991). Ponencias. [ s.n.].

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

International Consortium on Research in Science and Mathematics Education [3° : 1991 : Mérida, Yucatán]. Ponencias. Yucatán, México: [ s.n.], 1991.

MLA -ийн эшлэл (9 дэх хэвлэлт)

International Consortium on Research in Science and Mathematics Education [3° : 1991 : Mérida, Yucatán]. Ponencias. [ s.n.], 1991.