Böwering, G. (1979). The mystical vision of existence in classical Islam: The Qur'ānic hermeneutics of the Ṣūfī Sahl At-Tustarī (d. 283/896). Walter de Gruyter.
Chicago Style (17th ed.) CitationBöwering, Gerhard. The Mystical Vision of Existence in Classical Islam: The Qur'ānic Hermeneutics of the Ṣūfī Sahl At-Tustarī (d. 283/896). Berlin: Walter de Gruyter, 1979.
MLA (9th ed.) CitationBöwering, Gerhard. The Mystical Vision of Existence in Classical Islam: The Qur'ānic Hermeneutics of the Ṣūfī Sahl At-Tustarī (d. 283/896). Walter de Gruyter, 1979.
Warning: These citations may not always be 100% accurate.