[1] 世界時 - Wikipedia (2017-01-08 20:39:14 +09:00) https://ja.wikipedia.org/wiki/%E4%B8%96%E7%95%8C%E6%99%82#.E6.8E.A1.E7.94.A8.E7.B5.8C.E5.BA.A6.E7.B3.BB.E3.81.AE.E7.B5.B1.E4.B8.80.E3.81.A8.E6.85.A3.E7.94.A8.E5.9B.BD.E9.9A.9B.E5.8E.9F.E7.82.B9_.28CIO.29_.E3.81.AE.E6.8E.A1.E7.94.A8

[2] 国際地球基準座標系(International Terrestrial Reference System) (2005-02-17 19:37:32 +09:00) http://www2.nc-toyama.ac.jp/~mkawai/lecture/radionav/tfcoordinate/itrs/itrs.html

[3] 採用経度値と極原点 (2008-01-19 19:05:36 +09:00) http://www.asj.or.jp/geppou/archive_open/1969/pdf/19690508.pdf

[4] 極運動 - Wikipedia (2017-02-03 21:27:56 +09:00) https://ja.wikipedia.org/wiki/%E6%A5%B5%E9%81%8B%E5%8B%95