| APA | PES. (2012, February 14). In Acronym Geek. Retrieved 11:33, February 14, 2012, from http://www.acronymgeek.com/PES |
| MLA | "PES." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/PES>. |
| MHRA | 'PES', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/PES> [accessed 14 February 2012] |
| Chicago | "PES", http://www.acronymgeek.com/PES (accessed February 14, 2012). |
| CBE/CSE | PES [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/PES. |
| Bluebook | PES, http://www.acronymgeek.com/PES (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PES, http://www.acronymgeek.com/PES (optional description here) (as of Feb. 14, 2012, 11:33). |
| AMA | PES. Acronym Geek. February 14, 2012, 11:33. Available at: http://www.acronymgeek.com/PES. Accessed February 14, 2012, 11:33. |