| APA | HPN. (2012, February 15). In Acronym Geek. Retrieved 03:50, February 15, 2012, from http://www.acronymgeek.com/HPN |
| MLA | "HPN." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/HPN>. |
| MHRA | 'HPN', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/HPN> [accessed 15 February 2012] |
| Chicago | "HPN", http://www.acronymgeek.com/HPN (accessed February 15, 2012). |
| CBE/CSE | HPN [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/HPN. |
| Bluebook | HPN, http://www.acronymgeek.com/HPN (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HPN, http://www.acronymgeek.com/HPN (optional description here) (as of Feb. 15, 2012, 03:50). |
| AMA | HPN. Acronym Geek. February 15, 2012, 03:50. Available at: http://www.acronymgeek.com/HPN. Accessed February 15, 2012, 03:50. |