| APA | OECH. (2012, February 17). In Acronym Geek. Retrieved 00:44, February 17, 2012, from http://www.acronymgeek.com/OECH |
| MLA | "OECH." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/OECH>. |
| MHRA | 'OECH', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/OECH> [accessed 17 February 2012] |
| Chicago | "OECH", http://www.acronymgeek.com/OECH (accessed February 17, 2012). |
| CBE/CSE | OECH [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/OECH. |
| Bluebook | OECH, http://www.acronymgeek.com/OECH (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OECH, http://www.acronymgeek.com/OECH (optional description here) (as of Feb. 17, 2012, 00:44). |
| AMA | OECH. Acronym Geek. February 17, 2012, 00:44. Available at: http://www.acronymgeek.com/OECH. Accessed February 17, 2012, 00:44. |