Hoehn, R. G. (1995). Science puzzlers!: 150 ready-to-use activities to make learning fun : grades 4-8. Center for Applied Research in Education.
Čikaški stil citiranja (17. izdanje)Hoehn, Robert G. Science Puzzlers!: 150 Ready-to-use Activities to Make Learning Fun : Grades 4-8. West Nyack, N.Y: Center for Applied Research in Education, 1995.
MLA način citiranja (9. izdanje)Hoehn, Robert G. Science Puzzlers!: 150 Ready-to-use Activities to Make Learning Fun : Grades 4-8. Center for Applied Research in Education, 1995.
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