| APA | H4I. (2012, February 14). In Acronym Geek. Retrieved 10:25, February 14, 2012, from http://www.acronymgeek.com/H4I |
| MLA | "H4I." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/H4I>. |
| MHRA | 'H4I', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/H4I> [accessed 14 February 2012] |
| Chicago | "H4I", http://www.acronymgeek.com/H4I (accessed February 14, 2012). |
| CBE/CSE | H4I [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/H4I. |
| Bluebook | H4I, http://www.acronymgeek.com/H4I (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, H4I, http://www.acronymgeek.com/H4I (optional description here) (as of Feb. 14, 2012, 10:25). |
| AMA | H4I. Acronym Geek. February 14, 2012, 10:25. Available at: http://www.acronymgeek.com/H4I. Accessed February 14, 2012, 10:25. |