APA aipamena

Hoefer, H. J., & Hill, A. F. (1991). Portugal. APA Publications.

Chicago Style aipamena

Hoefer, Hans Johannes, and Alison Friesinger Hill. Portugal. Hong Kong: APA Publications, 1991.

MLA aipamena

Hoefer, Hans Johannes, and Alison Friesinger Hill. Portugal. APA Publications, 1991.