Hartley, R. E. (1952). Understanding children's Play. Columbia University Press.
シカゴスタイル引用形Hartley, Ruth E. Understanding Children's Play. New York: Columbia University Press, 1952.
MLA引用形式Hartley, Ruth E. Understanding Children's Play. Columbia University Press, 1952.
警告: この引用は必ずしも正確ではありません.