Escalante Araúz, P. (1991). The acquisition of twenty grammatical structures in children learning english as a foreign language in a Costa Rican bilingual elementary school. Escuela de Lenguas Modernas, Universidad de Costa Rica.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Escalante Araúz, Patricia. The Acquisition of Twenty Grammatical Structures in Children Learning English as a Foreign Language in a Costa Rican Bilingual Elementary School. San José, Costa Rica: Escuela de Lenguas Modernas, Universidad de Costa Rica, 1991.
Trích dẫn kiểu MLA (xuất bản lần thứ 9)Escalante Araúz, Patricia. The Acquisition of Twenty Grammatical Structures in Children Learning English as a Foreign Language in a Costa Rican Bilingual Elementary School. Escuela de Lenguas Modernas, Universidad de Costa Rica, 1991.