De La Pena, C. R. (1972). A study of difficulties in teaching elementary mathematics encountered by student teachers and interns of the Philippine Normal College.
Παραπομπή σε μορφή Chicago (17η εκδ.)De La Pena, Carmen Relunia. A Study of Difficulties in Teaching Elementary Mathematics Encountered by Student Teachers and Interns of the Philippine Normal College. 1972.
Παραπομπή σε μορφή MLA (9th εκδ.)De La Pena, Carmen Relunia. A Study of Difficulties in Teaching Elementary Mathematics Encountered by Student Teachers and Interns of the Philippine Normal College. 1972.
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