APA (7th ed.) Zitazioa
Houghton, P. (2002). Nine descents of the spirit: Towards inner harmony. Jessica Kingsley.
Chicago Style (17th ed.) Zitazioa
Houghton, Peter. Nine Descents of the Spirit: Towards Inner Harmony. London ; Philadelphia: Jessica Kingsley, 2002.
MLA (9th ed.) Zitazioa
Houghton, Peter. Nine Descents of the Spirit: Towards Inner Harmony. Jessica Kingsley, 2002.
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