Gutiérrez Font, R. (1993). Phonological defossilization in adult Spanish speakers learning english as a foreing language. Escuela de Lenguas Modernas, Universidad de Costa Rica.
Chicago-viite (17. p.)Gutiérrez Font, Roxana. Phonological Defossilization in Adult Spanish Speakers Learning English as a Foreing Language. San José, Costa Rica: Escuela de Lenguas Modernas, Universidad de Costa Rica, 1993.
MLA-viite (9. p.)Gutiérrez Font, Roxana. Phonological Defossilization in Adult Spanish Speakers Learning English as a Foreing Language. Escuela de Lenguas Modernas, Universidad de Costa Rica, 1993.
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