| APA | 2HD. (2012, February 10). In Acronym Geek. Retrieved 09:42, February 10, 2012, from http://www.acronymgeek.com/2HD |
| MLA | "2HD." Acronym Geek. (2012). Acronym Geek. 10 Feb 2012 <http://www.acronymgeek.com/2HD>. |
| MHRA | '2HD', Acronym Geek, 10 February 2012, <http://www.acronymgeek.com/2HD> [accessed 10 February 2012] |
| Chicago | "2HD", http://www.acronymgeek.com/2HD (accessed February 10, 2012). |
| CBE/CSE | 2HD [Internet]. Acronym Geek; 2012 Feb 10 [cited 2012 Feb 10]. Available from: http://www.acronymgeek.com/2HD. |
| Bluebook | 2HD, http://www.acronymgeek.com/2HD (last visited February 10, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, 2HD, http://www.acronymgeek.com/2HD (optional description here) (as of Feb. 10, 2012, 09:42). |
| AMA | 2HD. Acronym Geek. February 10, 2012, 09:42. Available at: http://www.acronymgeek.com/2HD. Accessed February 10, 2012, 09:42. |