| APA | PF. (2012, February 14). In Acronym Geek. Retrieved 06:21, February 14, 2012, from http://www.acronymgeek.com/PF |
| MLA | "PF." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/PF>. |
| MHRA | 'PF', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/PF> [accessed 14 February 2012] |
| Chicago | "PF", http://www.acronymgeek.com/PF (accessed February 14, 2012). |
| CBE/CSE | PF [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/PF. |
| Bluebook | PF, http://www.acronymgeek.com/PF (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PF, http://www.acronymgeek.com/PF (optional description here) (as of Feb. 14, 2012, 06:21). |
| AMA | PF. Acronym Geek. February 14, 2012, 06:21. Available at: http://www.acronymgeek.com/PF. Accessed February 14, 2012, 06:21. |