| APA | OPTT. (2012, February 15). In Acronym Geek. Retrieved 20:38, February 15, 2012, from http://www.acronymgeek.com/OPTT |
| MLA | "OPTT." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/OPTT>. |
| MHRA | 'OPTT', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/OPTT> [accessed 15 February 2012] |
| Chicago | "OPTT", http://www.acronymgeek.com/OPTT (accessed February 15, 2012). |
| CBE/CSE | OPTT [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/OPTT. |
| Bluebook | OPTT, http://www.acronymgeek.com/OPTT (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OPTT, http://www.acronymgeek.com/OPTT (optional description here) (as of Feb. 15, 2012, 20:38). |
| AMA | OPTT. Acronym Geek. February 15, 2012, 20:38. Available at: http://www.acronymgeek.com/OPTT. Accessed February 15, 2012, 20:38. |