| APA | HFK. (2012, February 14). In Acronym Geek. Retrieved 08:00, February 14, 2012, from http://www.acronymgeek.com/HFK |
| MLA | "HFK." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/HFK>. |
| MHRA | 'HFK', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/HFK> [accessed 14 February 2012] |
| Chicago | "HFK", http://www.acronymgeek.com/HFK (accessed February 14, 2012). |
| CBE/CSE | HFK [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/HFK. |
| Bluebook | HFK, http://www.acronymgeek.com/HFK (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HFK, http://www.acronymgeek.com/HFK (optional description here) (as of Feb. 14, 2012, 08:00). |
| AMA | HFK. Acronym Geek. February 14, 2012, 08:00. Available at: http://www.acronymgeek.com/HFK. Accessed February 14, 2012, 08:00. |