| APA | SDO. (2012, February 14). In Acronym Geek. Retrieved 19:13, February 14, 2012, from http://www.acronymgeek.com/SDO |
| MLA | "SDO." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/SDO>. |
| MHRA | 'SDO', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/SDO> [accessed 14 February 2012] |
| Chicago | "SDO", http://www.acronymgeek.com/SDO (accessed February 14, 2012). |
| CBE/CSE | SDO [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/SDO. |
| Bluebook | SDO, http://www.acronymgeek.com/SDO (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, SDO, http://www.acronymgeek.com/SDO (optional description here) (as of Feb. 14, 2012, 19:13). |
| AMA | SDO. Acronym Geek. February 14, 2012, 19:13. Available at: http://www.acronymgeek.com/SDO. Accessed February 14, 2012, 19:13. |