| APA | OCA. (2012, February 13). In Acronym Geek. Retrieved 20:51, February 13, 2012, from http://www.acronymgeek.com/OCA |
| MLA | "OCA." Acronym Geek. (2012). Acronym Geek. 13 Feb 2012 <http://www.acronymgeek.com/OCA>. |
| MHRA | 'OCA', Acronym Geek, 13 February 2012, <http://www.acronymgeek.com/OCA> [accessed 13 February 2012] |
| Chicago | "OCA", http://www.acronymgeek.com/OCA (accessed February 13, 2012). |
| CBE/CSE | OCA [Internet]. Acronym Geek; 2012 Feb 13 [cited 2012 Feb 13]. Available from: http://www.acronymgeek.com/OCA. |
| Bluebook | OCA, http://www.acronymgeek.com/OCA (last visited February 13, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OCA, http://www.acronymgeek.com/OCA (optional description here) (as of Feb. 13, 2012, 20:51). |
| AMA | OCA. Acronym Geek. February 13, 2012, 20:51. Available at: http://www.acronymgeek.com/OCA. Accessed February 13, 2012, 20:51. |