Rumble, G. The costs and economics of open and distance learning.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रRumble, Greville. The Costs and Economics of Open and Distance Learning.
एमएलए (8वां संस्करण) प्रशस्ति पत्रRumble, Greville. The Costs and Economics of Open and Distance Learning.
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