“Zuhud dan Etos Kerja Pengamal Tarekat Naqsyabandiyah Khalidiyah: Asceticism and Work Ethic of the Practitioners of the Naqshbandiyah Khalidiyah Order” (2007) Fenomena, 6(2), pp. 227–238. doi:10.35719/fenomena.v6i2.411.