| APA | U/O. (2012, February 12). In Acronym Geek. Retrieved 15:04, February 12, 2012, from http://www.acronymgeek.com/U/O |
| MLA | "U/O." Acronym Geek. (2012). Acronym Geek. 12 Feb 2012 <http://www.acronymgeek.com/U/O>. |
| MHRA | 'U/O', Acronym Geek, 12 February 2012, <http://www.acronymgeek.com/U/O> [accessed 12 February 2012] |
| Chicago | "U/O", http://www.acronymgeek.com/U/O (accessed February 12, 2012). |
| CBE/CSE | U/O [Internet]. Acronym Geek; 2012 Feb 12 [cited 2012 Feb 12]. Available from: http://www.acronymgeek.com/U/O. |
| Bluebook | U/O, http://www.acronymgeek.com/U/O (last visited February 12, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, U/O, http://www.acronymgeek.com/U/O (optional description here) (as of Feb. 12, 2012, 15:04). |
| AMA | U/O. Acronym Geek. February 12, 2012, 15:04. Available at: http://www.acronymgeek.com/U/O. Accessed February 12, 2012, 15:04. |