| APA | PID. (2012, February 14). In Acronym Geek. Retrieved 10:27, February 14, 2012, from http://www.acronymgeek.com/PID |
| MLA | "PID." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/PID>. |
| MHRA | 'PID', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/PID> [accessed 14 February 2012] |
| Chicago | "PID", http://www.acronymgeek.com/PID (accessed February 14, 2012). |
| CBE/CSE | PID [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/PID. |
| Bluebook | PID, http://www.acronymgeek.com/PID (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PID, http://www.acronymgeek.com/PID (optional description here) (as of Feb. 14, 2012, 10:27). |
| AMA | PID. Acronym Geek. February 14, 2012, 10:27. Available at: http://www.acronymgeek.com/PID. Accessed February 14, 2012, 10:27. |