| APA | USYS. (2012, February 15). In Acronym Geek. Retrieved 00:04, February 15, 2012, from http://www.acronymgeek.com/USYS |
| MLA | "USYS." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/USYS>. |
| MHRA | 'USYS', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/USYS> [accessed 15 February 2012] |
| Chicago | "USYS", http://www.acronymgeek.com/USYS (accessed February 15, 2012). |
| CBE/CSE | USYS [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/USYS. |
| Bluebook | USYS, http://www.acronymgeek.com/USYS (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, USYS, http://www.acronymgeek.com/USYS (optional description here) (as of Feb. 15, 2012, 00:04). |
| AMA | USYS. Acronym Geek. February 15, 2012, 00:04. Available at: http://www.acronymgeek.com/USYS. Accessed February 15, 2012, 00:04. |