Pili, I. B. (1977). A survey of completed descriptive and contrastive researches on teaching English as a second language from 1959 to 1971 [microform]. Photoduplication Service.University of the Philippines Library.
Lua i Stíl Chicago (17ú heag.)Pili, Irene B. A Survey of Completed Descriptive and Contrastive Researches on Teaching English as a Second Language from 1959 to 1971 [microform]. Quezon City: Photoduplication Service.University of the Philippines Library, 1977.
Lua MLA (9ú heag.)Pili, Irene B. A Survey of Completed Descriptive and Contrastive Researches on Teaching English as a Second Language from 1959 to 1971 [microform]. Photoduplication Service.University of the Philippines Library, 1977.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.