Hairston, N. G. (1989). Ecological experiences: Purpose, design and execution. Cambridge University Press.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रHairston, Nelson G. Ecological Experiences: Purpose, Design and Execution. Cambridge: Cambridge University Press, 1989.
एमएलए (9वां संस्करण) प्रशस्ति पत्रHairston, Nelson G. Ecological Experiences: Purpose, Design and Execution. Cambridge University Press, 1989.
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