Harlan, J. D. (1976). Science experimences for the early childhood years. Charles E. Merrill Publ.
Chicago-viite (17. p.)Harlan, Jean Durgin. Science Experimences for the Early Childhood Years. Charles E. Merrill Publ, 1976.
MLA-viite (8. p.)Harlan, Jean Durgin. Science Experimences for the Early Childhood Years. Charles E. Merrill Publ, 1976.
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