| APA | OUDN. (2012, February 14). In Acronym Geek. Retrieved 14:03, February 14, 2012, from http://www.acronymgeek.com/OUDN |
| MLA | "OUDN." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/OUDN>. |
| MHRA | 'OUDN', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/OUDN> [accessed 14 February 2012] |
| Chicago | "OUDN", http://www.acronymgeek.com/OUDN (accessed February 14, 2012). |
| CBE/CSE | OUDN [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/OUDN. |
| Bluebook | OUDN, http://www.acronymgeek.com/OUDN (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OUDN, http://www.acronymgeek.com/OUDN (optional description here) (as of Feb. 14, 2012, 14:03). |
| AMA | OUDN. Acronym Geek. February 14, 2012, 14:03. Available at: http://www.acronymgeek.com/OUDN. Accessed February 14, 2012, 14:03. |