| APA | HPPI. (2012, February 15). In Acronym Geek. Retrieved 05:33, February 15, 2012, from http://www.acronymgeek.com/HPPI |
| MLA | "HPPI." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/HPPI>. |
| MHRA | 'HPPI', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/HPPI> [accessed 15 February 2012] |
| Chicago | "HPPI", http://www.acronymgeek.com/HPPI (accessed February 15, 2012). |
| CBE/CSE | HPPI [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/HPPI. |
| Bluebook | HPPI, http://www.acronymgeek.com/HPPI (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HPPI, http://www.acronymgeek.com/HPPI (optional description here) (as of Feb. 15, 2012, 05:33). |
| AMA | HPPI. Acronym Geek. February 15, 2012, 05:33. Available at: http://www.acronymgeek.com/HPPI. Accessed February 15, 2012, 05:33. |