| APA | O/R. (2012, February 9). In Acronym Geek. Retrieved 21:41, February 9, 2012, from http://www.acronymgeek.com/O/R |
| MLA | "O/R." Acronym Geek. (2012). Acronym Geek. 9 Feb 2012 <http://www.acronymgeek.com/O/R>. |
| MHRA | 'O/R', Acronym Geek, 9 February 2012, <http://www.acronymgeek.com/O/R> [accessed 9 February 2012] |
| Chicago | "O/R", http://www.acronymgeek.com/O/R (accessed February 9, 2012). |
| CBE/CSE | O/R [Internet]. Acronym Geek; 2012 Feb 9 [cited 2012 Feb 9]. Available from: http://www.acronymgeek.com/O/R. |
| Bluebook | O/R, http://www.acronymgeek.com/O/R (last visited February 9, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, O/R, http://www.acronymgeek.com/O/R (optional description here) (as of Feb. 9, 2012, 21:41). |
| AMA | O/R. Acronym Geek. February 9, 2012, 21:41. Available at: http://www.acronymgeek.com/O/R. Accessed February 9, 2012, 21:41. |