| APA | URDO. (2012, February 14). In Acronym Geek. Retrieved 13:55, February 14, 2012, from http://www.acronymgeek.com/URDO |
| MLA | "URDO." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/URDO>. |
| MHRA | 'URDO', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/URDO> [accessed 14 February 2012] |
| Chicago | "URDO", http://www.acronymgeek.com/URDO (accessed February 14, 2012). |
| CBE/CSE | URDO [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/URDO. |
| Bluebook | URDO, http://www.acronymgeek.com/URDO (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, URDO, http://www.acronymgeek.com/URDO (optional description here) (as of Feb. 14, 2012, 13:55). |
| AMA | URDO. Acronym Geek. February 14, 2012, 13:55. Available at: http://www.acronymgeek.com/URDO. Accessed February 14, 2012, 13:55. |