Jay M. Pasachoff, Glenn Schneider, and Leon Golub (June 2004). “The black-drop effect explained”. Proceedings of the International Astronomical Union (International Astronomical Union) (196): 243–244. doi:10.1017/S1743921305001420.
Christine Allen (2004). “The Mexican expedition to observe the 8 December 1874 transit of Venus in Japan”. Proceedings of the International Astronomical Union (International Astronomical Union) (196): 111–123. doi:10.1017/S1743921305001316.
economist.com
“Kiss of the goddess”. The Economist. The Economist Newspaper Limited (2004年5月27日). 2016年3月20日閲覧。