Murray Milner, Jr.. Elites: A General Model. John Wiley & Sons, 8 gener 2015, p. 62. ISBN 978-0-7456-8950-0. «Greece has long been considered the seedbed or cradle of Western civilization.»
Kim Covert. Ancient Greece: Birthplace of Democracy. Capstone, 1 juliol 2011, p. 5. ISBN 978-1-4296-6831-6. «Ancient Greece is often called the cradle of western civilization. ... Ideas from literature and science also have their roots in ancient Greece.»
Lin (林), Shengyi (勝義); He (何), Xianrong (顯榮). Taiwan — The Cradle of Civilization (en chinese). Taipei: Taiwan fei die xue yan jiu hui (台灣飛碟學硏究會), 2001. ISBN 978-957-30188-0-3. OCLC52945170.
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«Civilization». The Columbia Encyclopedia. Arxivat de l'original el 2012-07-08. [Consulta: 28 juliol 2008].