APA (7th ed.) Zitazioa
Collins, G. R. (1991). Excellence and ethics in counseling. Word.
Chicago Style (17th ed.) Zitazioa
Collins, Gary R. Excellence and Ethics in Counseling. [Dallas]: Word, 1991.
MLA (9th ed.) Zitazioa
Collins, Gary R. Excellence and Ethics in Counseling. Word, 1991.
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