| APA | SPEF. (2012, February 16). In Acronym Geek. Retrieved 17:49, February 16, 2012, from http://www.acronymgeek.com/SPEF |
| MLA | "SPEF." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/SPEF>. |
| MHRA | 'SPEF', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/SPEF> [accessed 16 February 2012] |
| Chicago | "SPEF", http://www.acronymgeek.com/SPEF (accessed February 16, 2012). |
| CBE/CSE | SPEF [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/SPEF. |
| Bluebook | SPEF, http://www.acronymgeek.com/SPEF (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, SPEF, http://www.acronymgeek.com/SPEF (optional description here) (as of Feb. 16, 2012, 17:49). |
| AMA | SPEF. Acronym Geek. February 16, 2012, 17:49. Available at: http://www.acronymgeek.com/SPEF. Accessed February 16, 2012, 17:49. |