| APA | HFEN. (2012, February 16). In Acronym Geek. Retrieved 23:33, February 16, 2012, from http://www.acronymgeek.com/HFEN |
| MLA | "HFEN." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/HFEN>. |
| MHRA | 'HFEN', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/HFEN> [accessed 16 February 2012] |
| Chicago | "HFEN", http://www.acronymgeek.com/HFEN (accessed February 16, 2012). |
| CBE/CSE | HFEN [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/HFEN. |
| Bluebook | HFEN, http://www.acronymgeek.com/HFEN (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HFEN, http://www.acronymgeek.com/HFEN (optional description here) (as of Feb. 16, 2012, 23:33). |
| AMA | HFEN. Acronym Geek. February 16, 2012, 23:33. Available at: http://www.acronymgeek.com/HFEN. Accessed February 16, 2012, 23:33. |