| APA | PDD. (2012, February 14). In Acronym Geek. Retrieved 10:06, February 14, 2012, from http://www.acronymgeek.com/PDD |
| MLA | "PDD." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/PDD>. |
| MHRA | 'PDD', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/PDD> [accessed 14 February 2012] |
| Chicago | "PDD", http://www.acronymgeek.com/PDD (accessed February 14, 2012). |
| CBE/CSE | PDD [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/PDD. |
| Bluebook | PDD, http://www.acronymgeek.com/PDD (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PDD, http://www.acronymgeek.com/PDD (optional description here) (as of Feb. 14, 2012, 10:06). |
| AMA | PDD. Acronym Geek. February 14, 2012, 10:06. Available at: http://www.acronymgeek.com/PDD. Accessed February 14, 2012, 10:06. |