| APA | P.D.. (2012, February 15). In Acronym Geek. Retrieved 05:19, February 15, 2012, from http://www.acronymgeek.com/P.D. |
| MLA | "P.D.." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/P.D.>. |
| MHRA | 'P.D.', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/P.D.> [accessed 15 February 2012] |
| Chicago | "P.D.", http://www.acronymgeek.com/P.D. (accessed February 15, 2012). |
| CBE/CSE | P.D. [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/P.D.. |
| Bluebook | P.D., http://www.acronymgeek.com/P.D. (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, P.D., http://www.acronymgeek.com/P.D. (optional description here) (as of Feb. 15, 2012, 05:19). |
| AMA | P.D.. Acronym Geek. February 15, 2012, 05:19. Available at: http://www.acronymgeek.com/P.D.. Accessed February 15, 2012, 05:19. |