APA-referens (7:e uppl.)

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.

Chicago-referens (17:e uppl.)

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.

MLA-referens (9:e uppl.)

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.

Varning: dessa hänvisningar är inte alltid fullständigt riktiga.