IAU resolutions adopted at the XVIth General Assembly, Grenoble, France, 1976(PDF). 1976 [2014-02-02]. (原始内容存档(PDF)于2019-05-02). Resolution no. 3 by Commissions 4 (Ephemerides/Ephémérides) and 31 (Time/L'Heure) (near the end of the document) "recommend that the following notations be used in all languages", UT0(i), UT1(i), UT2(i), UTC, UTC(i), UT, where (i) is institution "i".
IAU resolutions adopted at the XVIth General Assembly, Grenoble, France, 1976(PDF). 1976 [2014-02-02]. (原始内容存档(PDF)于2019-05-02). Resolution no. 3 by Commissions 4 (Ephemerides/Ephémérides) and 31 (Time/L'Heure) (near the end of the document) "recommend that the following notations be used in all languages", UT0(i), UT1(i), UT2(i), UTC, UTC(i), UT, where (i) is institution "i".