| APA | PTHL. (2012, February 16). In Acronym Geek. Retrieved 04:59, February 16, 2012, from http://www.acronymgeek.com/PTHL |
| MLA | "PTHL." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/PTHL>. |
| MHRA | 'PTHL', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/PTHL> [accessed 16 February 2012] |
| Chicago | "PTHL", http://www.acronymgeek.com/PTHL (accessed February 16, 2012). |
| CBE/CSE | PTHL [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/PTHL. |
| Bluebook | PTHL, http://www.acronymgeek.com/PTHL (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PTHL, http://www.acronymgeek.com/PTHL (optional description here) (as of Feb. 16, 2012, 04:59). |
| AMA | PTHL. Acronym Geek. February 16, 2012, 04:59. Available at: http://www.acronymgeek.com/PTHL. Accessed February 16, 2012, 04:59. |