On the re-definition of the astronomical unit of length(PDF). XXVIII General Assembly of International Astronomical Union. Beijing, China: International Astronomical Union. 31. 8. 2012. Resolution B2. „... recommends ... 5. that the unique symbol "au" be used for the astronomical unit.”CS1 одржавање: Формат датума (веза)
On the re-definition of the astronomical unit of length(PDF). XXVIII General Assembly of International Astronomical Union. Beijing: International Astronomical Union. 31. 8. 2012. Resolution B2. „... recommends [adopted] that the astronomical unit be re-defined to be a conventional unit of length equal to exactly 149,597,870,700 metres, in agreement with the value adopted in IAU 2009 Resolution B2”CS1 одржавање: Формат датума (веза)
Commission 4: Ephemerides/Ephémérides (1976). item 12: Unit distance(PDF). XVIth General Assembly of the International Astronomical Union. IAU (1976) System of Astronomical Constants. Grenoble, FR. Commission 4, part III, Recommendation 1, item 12.
„Instructions to Authors”. Monthly Notices of the Royal Astronomical Society. Oxford University Press. Приступљено 5. 11. 2020. „The units of length/distance are Å, nm, µm, mm, cm, m, km, au, light-year, pc.”CS1 одржавање: Формат датума (веза)