| APA | IFEN. (2012, February 16). In Acronym Geek. Retrieved 21:26, February 16, 2012, from http://www.acronymgeek.com/IFEN |
| MLA | "IFEN." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/IFEN>. |
| MHRA | 'IFEN', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/IFEN> [accessed 16 February 2012] |
| Chicago | "IFEN", http://www.acronymgeek.com/IFEN (accessed February 16, 2012). |
| CBE/CSE | IFEN [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/IFEN. |
| Bluebook | IFEN, http://www.acronymgeek.com/IFEN (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, IFEN, http://www.acronymgeek.com/IFEN (optional description here) (as of Feb. 16, 2012, 21:26). |
| AMA | IFEN. Acronym Geek. February 16, 2012, 21:26. Available at: http://www.acronymgeek.com/IFEN. Accessed February 16, 2012, 21:26. |