Rogacion, M. R. E. (1991). Knowing yourself and others: The eastern enneagram. Rex Book Store.
Lua i Stíl Chicago (17ú heag.)Rogacion, Mary Rebecca E. Knowing Yourself and Others: The Eastern Enneagram. Manila: Rex Book Store, 1991.
Lua MLA (9ú heag.)Rogacion, Mary Rebecca E. Knowing Yourself and Others: The Eastern Enneagram. Rex Book Store, 1991.
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