| APA | PKN. (2012, February 14). In Acronym Geek. Retrieved 10:35, February 14, 2012, from http://www.acronymgeek.com/PKN |
| MLA | "PKN." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/PKN>. |
| MHRA | 'PKN', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/PKN> [accessed 14 February 2012] |
| Chicago | "PKN", http://www.acronymgeek.com/PKN (accessed February 14, 2012). |
| CBE/CSE | PKN [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/PKN. |
| Bluebook | PKN, http://www.acronymgeek.com/PKN (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PKN, http://www.acronymgeek.com/PKN (optional description here) (as of Feb. 14, 2012, 10:35). |
| AMA | PKN. Acronym Geek. February 14, 2012, 10:35. Available at: http://www.acronymgeek.com/PKN. Accessed February 14, 2012, 10:35. |