Zezong, Xi, "The Discovery of Jupiter's Satellite Made by Gan De 2000 years Before Galileo", Chinese Physics 2 (3) (1982): 664–67.
2007년 8월 9일에 확인함.  Zezong, Xi, "The Discovery of Jupiter's Satellite Made by Gan De 2000 years Before Galileo", Chinese Physics 2 (3) (1982): 664–67.