Buettner, D. (2017). The blue zones of happiness: Lessons from the world's happiest people. National Geographic.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBuettner, Dan. The Blue Zones of Happiness: Lessons from the World's Happiest People. Washington, D.C.: National Geographic, 2017.
एमएलए (8वां संस्करण) प्रशस्ति पत्रBuettner, Dan. The Blue Zones of Happiness: Lessons from the World's Happiest People. National Geographic, 2017.
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