| APA | XEF. (2012, February 14). In Acronym Geek. Retrieved 11:35, February 14, 2012, from http://www.acronymgeek.com/XEF |
| MLA | "XEF." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/XEF>. |
| MHRA | 'XEF', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/XEF> [accessed 14 February 2012] |
| Chicago | "XEF", http://www.acronymgeek.com/XEF (accessed February 14, 2012). |
| CBE/CSE | XEF [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/XEF. |
| Bluebook | XEF, http://www.acronymgeek.com/XEF (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, XEF, http://www.acronymgeek.com/XEF (optional description here) (as of Feb. 14, 2012, 11:35). |
| AMA | XEF. Acronym Geek. February 14, 2012, 11:35. Available at: http://www.acronymgeek.com/XEF. Accessed February 14, 2012, 11:35. |