Powell, Robert, Influence of Babylonian Astronomy on the Subsequent Defining of the Zodiac (2004), PhD thesis, summarized by anonymous editor, Archived 21 May 2009 at the Wayback Machine.
Powell, Robert, Influence of Babylonian Astronomy on the Subsequent Defining of the Zodiac →황도대의 계속되는 정의에 미치는 바빌로니아 황도대의 영향력(2004), PhD thesis, summarized by anonymous editor, Wayback version.