| APA | HTPLO. (2012, February 12). In Acronym Geek. Retrieved 12:16, February 12, 2012, from http://www.acronymgeek.com/HTPLO |
| MLA | "HTPLO." Acronym Geek. (2012). Acronym Geek. 12 Feb 2012 <http://www.acronymgeek.com/HTPLO>. |
| MHRA | 'HTPLO', Acronym Geek, 12 February 2012, <http://www.acronymgeek.com/HTPLO> [accessed 12 February 2012] |
| Chicago | "HTPLO", http://www.acronymgeek.com/HTPLO (accessed February 12, 2012). |
| CBE/CSE | HTPLO [Internet]. Acronym Geek; 2012 Feb 12 [cited 2012 Feb 12]. Available from: http://www.acronymgeek.com/HTPLO. |
| Bluebook | HTPLO, http://www.acronymgeek.com/HTPLO (last visited February 12, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HTPLO, http://www.acronymgeek.com/HTPLO (optional description here) (as of Feb. 12, 2012, 12:16). |
| AMA | HTPLO. Acronym Geek. February 12, 2012, 12:16. Available at: http://www.acronymgeek.com/HTPLO. Accessed February 12, 2012, 12:16. |