(2015). O's little book of happiness (First edition.). Flatiron Books.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रO's Little Book of Happiness. First edition. New York: Flatiron Books, 2015.
एमएलए (8वां संस्करण) प्रशस्ति पत्रO's Little Book of Happiness. First edition. Flatiron Books, 2015.
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