Pelligrini, Anthony D.
Observing children in their Natural worlds : a methodological primer
Lawrence Elbaum Associates, 1996
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Grant, P. James
The state of the world's children 1986
Oxford University Press, 1986
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Russell, Richard Joel
Culture worlds
Macmillan, 1954, 1951
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Russell, Richard Joel
Culture worlds
Macmillan, 1958
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Worlds Apart
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