AXLINE, V. M. (1947). Play therapy. Boston: Houghton Mifflin .
2.
DEUTSCH, M. (1949). An experimental study of the effects of cooperation and competition upon group processes . Hum. relat.2, 199-231 .
3.
EIFERMANN, R. R. (1970). Level of children's play as expressed in group size . Brit. j ed. psychol.40, (2), 161-170 .
4.
EIFERMANN, R. R. (In press, a). Determinants of children's game styles. Jerusalem: The Israel Academy of Sciences and Humanities .
5.
EIFERMANN, R. R. (In press, b). Social play in childhood. In: R. E. Heron & B. Sutton-Smith (eds), Childs play. New York: Wiley .
6.
GROOS, K. (1901). The play of man. (First German edition, 1899.) New York: Appleton & Co .
7.
PIAGET, J. (1962). Play, dreams and imitation in childhood. (First French edition, 1951.) London: Heinemann .
8.
PELLER, L. E. (1954). Libidinal phases, ego development, and play . Psychoanal. study of the childIX, 178-198 .
9.
RAVEN, B. M. & LEFF, W. F. (1965). The effects of partner's behavior and culture upon strategy in a two-person game. In: R. R. Eifermann (ed.), Studies in psychology, Scripta hierosoly mitana 14, 148-165. Jerusalem: The Hebrew University .
10.
SPIRO, M. E. (1958). Children of the kibbutz. Cambridge, Mass.: Harvard University Press .