(2005). Constructivist foundations: CF. Vrije University.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रConstructivist Foundations: CF. Brussels, Belgium: Vrije University, 2005.
एमएलए (9वां संस्करण) प्रशस्ति पत्रConstructivist Foundations: CF. Vrije University, 2005.
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