| APA | PDEN. (2012, February 16). In Acronym Geek. Retrieved 19:40, February 16, 2012, from http://www.acronymgeek.com/PDEN |
| MLA | "PDEN." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/PDEN>. |
| MHRA | 'PDEN', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/PDEN> [accessed 16 February 2012] |
| Chicago | "PDEN", http://www.acronymgeek.com/PDEN (accessed February 16, 2012). |
| CBE/CSE | PDEN [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/PDEN. |
| Bluebook | PDEN, http://www.acronymgeek.com/PDEN (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PDEN, http://www.acronymgeek.com/PDEN (optional description here) (as of Feb. 16, 2012, 19:40). |
| AMA | PDEN. Acronym Geek. February 16, 2012, 19:40. Available at: http://www.acronymgeek.com/PDEN. Accessed February 16, 2012, 19:40. |