| APA | PEF. (2012, February 14). In Acronym Geek. Retrieved 19:26, February 14, 2012, from http://www.acronymgeek.com/PEF |
| MLA | "PEF." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/PEF>. |
| MHRA | 'PEF', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/PEF> [accessed 14 February 2012] |
| Chicago | "PEF", http://www.acronymgeek.com/PEF (accessed February 14, 2012). |
| CBE/CSE | PEF [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/PEF. |
| Bluebook | PEF, http://www.acronymgeek.com/PEF (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PEF, http://www.acronymgeek.com/PEF (optional description here) (as of Feb. 14, 2012, 19:26). |
| AMA | PEF. Acronym Geek. February 14, 2012, 19:26. Available at: http://www.acronymgeek.com/PEF. Accessed February 14, 2012, 19:26. |