Millis, R.L; Wasserman, Bowell, Franz, Klemola, Dunham. The diameter of 375 URSULA from its occultation of AG + 39 deg 303. Astronomical Journal. 1984, 89: 592–596. Bibcode:1984AJ.....89..592M. doi:10.1086/113553.引文使用过时参数coauthors (帮助)
harvard.edu
ui.adsabs.harvard.edu
Millis, R.L; Wasserman, Bowell, Franz, Klemola, Dunham. The diameter of 375 URSULA from its occultation of AG + 39 deg 303. Astronomical Journal. 1984, 89: 592–596. Bibcode:1984AJ.....89..592M. doi:10.1086/113553.引文使用过时参数coauthors (帮助)
minorplanetcenter.net
375 Ursula. Minor Planet Center. [28 March 2018]. (原始内容存档于2018-01-24).