| APA | OTPH. (2012, February 17). In Acronym Geek. Retrieved 00:11, February 17, 2012, from http://www.acronymgeek.com/OTPH |
| MLA | "OTPH." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/OTPH>. |
| MHRA | 'OTPH', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/OTPH> [accessed 17 February 2012] |
| Chicago | "OTPH", http://www.acronymgeek.com/OTPH (accessed February 17, 2012). |
| CBE/CSE | OTPH [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/OTPH. |
| Bluebook | OTPH, http://www.acronymgeek.com/OTPH (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OTPH, http://www.acronymgeek.com/OTPH (optional description here) (as of Feb. 17, 2012, 00:11). |
| AMA | OTPH. Acronym Geek. February 17, 2012, 00:11. Available at: http://www.acronymgeek.com/OTPH. Accessed February 17, 2012, 00:11. |