International Consortium on Research in Science and Mathematics Education [3° : 1991 : Mérida, Yucatán]. (1991). Ponencias. [ s.n.].
Chicago-viite (17. p.)International Consortium on Research in Science and Mathematics Education [3° : 1991 : Mérida, Yucatán]. Ponencias. Yucatán, México: [ s.n.], 1991.
MLA-viite (9. p.)International Consortium on Research in Science and Mathematics Education [3° : 1991 : Mérida, Yucatán]. Ponencias. [ s.n.], 1991.
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