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