| APA | HDRO. (2012, February 17). In Acronym Geek. Retrieved 01:13, February 17, 2012, from http://www.acronymgeek.com/HDRO |
| MLA | "HDRO." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/HDRO>. |
| MHRA | 'HDRO', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/HDRO> [accessed 17 February 2012] |
| Chicago | "HDRO", http://www.acronymgeek.com/HDRO (accessed February 17, 2012). |
| CBE/CSE | HDRO [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/HDRO. |
| Bluebook | HDRO, http://www.acronymgeek.com/HDRO (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HDRO, http://www.acronymgeek.com/HDRO (optional description here) (as of Feb. 17, 2012, 01:13). |
| AMA | HDRO. Acronym Geek. February 17, 2012, 01:13. Available at: http://www.acronymgeek.com/HDRO. Accessed February 17, 2012, 01:13. |