| APA | SYI. (2012, February 13). In Acronym Geek. Retrieved 21:13, February 13, 2012, from http://www.acronymgeek.com/SYI |
| MLA | "SYI." Acronym Geek. (2012). Acronym Geek. 13 Feb 2012 <http://www.acronymgeek.com/SYI>. |
| MHRA | 'SYI', Acronym Geek, 13 February 2012, <http://www.acronymgeek.com/SYI> [accessed 13 February 2012] |
| Chicago | "SYI", http://www.acronymgeek.com/SYI (accessed February 13, 2012). |
| CBE/CSE | SYI [Internet]. Acronym Geek; 2012 Feb 13 [cited 2012 Feb 13]. Available from: http://www.acronymgeek.com/SYI. |
| Bluebook | SYI, http://www.acronymgeek.com/SYI (last visited February 13, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, SYI, http://www.acronymgeek.com/SYI (optional description here) (as of Feb. 13, 2012, 21:13). |
| AMA | SYI. Acronym Geek. February 13, 2012, 21:13. Available at: http://www.acronymgeek.com/SYI. Accessed February 13, 2012, 21:13. |