| APA | OEP. (2012, February 14). In Acronym Geek. Retrieved 09:52, February 14, 2012, from http://www.acronymgeek.com/OEP |
| MLA | "OEP." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/OEP>. |
| MHRA | 'OEP', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/OEP> [accessed 14 February 2012] |
| Chicago | "OEP", http://www.acronymgeek.com/OEP (accessed February 14, 2012). |
| CBE/CSE | OEP [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/OEP. |
| Bluebook | OEP, http://www.acronymgeek.com/OEP (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OEP, http://www.acronymgeek.com/OEP (optional description here) (as of Feb. 14, 2012, 09:52). |
| AMA | OEP. Acronym Geek. February 14, 2012, 09:52. Available at: http://www.acronymgeek.com/OEP. Accessed February 14, 2012, 09:52. |