| APA | UPKI. (2012, February 14). In Acronym Geek. Retrieved 00:32, February 14, 2012, from http://www.acronymgeek.com/UPKI |
| MLA | "UPKI." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/UPKI>. |
| MHRA | 'UPKI', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/UPKI> [accessed 14 February 2012] |
| Chicago | "UPKI", http://www.acronymgeek.com/UPKI (accessed February 14, 2012). |
| CBE/CSE | UPKI [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/UPKI. |
| Bluebook | UPKI, http://www.acronymgeek.com/UPKI (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, UPKI, http://www.acronymgeek.com/UPKI (optional description here) (as of Feb. 14, 2012, 00:32). |
| AMA | UPKI. Acronym Geek. February 14, 2012, 00:32. Available at: http://www.acronymgeek.com/UPKI. Accessed February 14, 2012, 00:32. |