| APA | SD. (2012, February 14). In Acronym Geek. Retrieved 06:09, February 14, 2012, from http://www.acronymgeek.com/SD |
| MLA | "SD." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/SD>. |
| MHRA | 'SD', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/SD> [accessed 14 February 2012] |
| Chicago | "SD", http://www.acronymgeek.com/SD (accessed February 14, 2012). |
| CBE/CSE | SD [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/SD. |
| Bluebook | SD, http://www.acronymgeek.com/SD (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, SD, http://www.acronymgeek.com/SD (optional description here) (as of Feb. 14, 2012, 06:09). |
| AMA | SD. Acronym Geek. February 14, 2012, 06:09. Available at: http://www.acronymgeek.com/SD. Accessed February 14, 2012, 06:09. |