| APA | ONCE. (2012, February 17). In Acronym Geek. Retrieved 01:39, February 17, 2012, from http://www.acronymgeek.com/ONCE |
| MLA | "ONCE." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/ONCE>. |
| MHRA | 'ONCE', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/ONCE> [accessed 17 February 2012] |
| Chicago | "ONCE", http://www.acronymgeek.com/ONCE (accessed February 17, 2012). |
| CBE/CSE | ONCE [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/ONCE. |
| Bluebook | ONCE, http://www.acronymgeek.com/ONCE (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, ONCE, http://www.acronymgeek.com/ONCE (optional description here) (as of Feb. 17, 2012, 01:39). |
| AMA | ONCE. Acronym Geek. February 17, 2012, 01:39. Available at: http://www.acronymgeek.com/ONCE. Accessed February 17, 2012, 01:39. |