Bray, M. (1999). The shadow education system: Private tutoring and its implications for planners. Unesco, International Institute for Educational Planning.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBray, Mark. The Shadow Education System: Private Tutoring and Its Implications for Planners. Paris: Unesco, International Institute for Educational Planning, 1999.
एमएलए (9वां संस्करण) प्रशस्ति पत्रBray, Mark. The Shadow Education System: Private Tutoring and Its Implications for Planners. Unesco, International Institute for Educational Planning, 1999.
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