| APA | 2S. (2012, February 10). In Acronym Geek. Retrieved 10:41, February 10, 2012, from http://www.acronymgeek.com/2S |
| MLA | "2S." Acronym Geek. (2012). Acronym Geek. 10 Feb 2012 <http://www.acronymgeek.com/2S>. |
| MHRA | '2S', Acronym Geek, 10 February 2012, <http://www.acronymgeek.com/2S> [accessed 10 February 2012] |
| Chicago | "2S", http://www.acronymgeek.com/2S (accessed February 10, 2012). |
| CBE/CSE | 2S [Internet]. Acronym Geek; 2012 Feb 10 [cited 2012 Feb 10]. Available from: http://www.acronymgeek.com/2S. |
| Bluebook | 2S, http://www.acronymgeek.com/2S (last visited February 10, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, 2S, http://www.acronymgeek.com/2S (optional description here) (as of Feb. 10, 2012, 10:41). |
| AMA | 2S. Acronym Geek. February 10, 2012, 10:41. Available at: http://www.acronymgeek.com/2S. Accessed February 10, 2012, 10:41. |