Orejana, E. N. (1981). The relationship between some personal and environmental factors and children's performance on some Piagetian tasks: A concluding issue of the Review of Philippine Studies based on Piagets theory of cognitive development. Research Center, Philippine Normal College.
Lua i Stíl Chicago (17ú heag.)Orejana, Evelyn N. The Relationship Between Some Personal and Environmental Factors and Children's Performance on Some Piagetian Tasks: A Concluding Issue of the Review of Philippine Studies Based on Piagets Theory of Cognitive Development. Manila: Research Center, Philippine Normal College, 1981.
Lua MLA (9ú heag.)Orejana, Evelyn N. The Relationship Between Some Personal and Environmental Factors and Children's Performance on Some Piagetian Tasks: A Concluding Issue of the Review of Philippine Studies Based on Piagets Theory of Cognitive Development. Research Center, Philippine Normal College, 1981.