Orejana, E. N. (1980). The child's conception of space: A review of Philippine studies on the development of space concepts among Filipino children. Research Center, Philippine Normal College.
Chicago-viite (17. p.)Orejana, Evelyn N. The Child's Conception of Space: A Review of Philippine Studies on the Development of Space Concepts Among Filipino Children. Manila: Research Center, Philippine Normal College, 1980.
MLA-viite (9. p.)Orejana, Evelyn N. The Child's Conception of Space: A Review of Philippine Studies on the Development of Space Concepts Among Filipino Children. Research Center, Philippine Normal College, 1980.
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