Cusack, Carole. “Petsche, Johanna J. M. 2015. Gurdjieff and Music: The Gurdjieff De Hartmann Piano Music and Its Esoteric Significance. Leiden and Boston, MA: Brill. Xvi + 279pp. Ebook. US$130. E-ISBN: 9789004284449. Hbk. US$142.00. ISBN-13: 96789004284425”. Fieldwork in Religion 11, no. 1 (November 7, 2016): 121–122. Accessed November 21, 2024. https://journal.equinoxpub.com/FIR/article/view/13004.