| APA | ETUN. (2012, February 14). In Acronym Geek. Retrieved 18:51, February 14, 2012, from http://www.acronymgeek.com/ETUN |
| MLA | "ETUN." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/ETUN>. |
| MHRA | 'ETUN', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/ETUN> [accessed 14 February 2012] |
| Chicago | "ETUN", http://www.acronymgeek.com/ETUN (accessed February 14, 2012). |
| CBE/CSE | ETUN [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/ETUN. |
| Bluebook | ETUN, http://www.acronymgeek.com/ETUN (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, ETUN, http://www.acronymgeek.com/ETUN (optional description here) (as of Feb. 14, 2012, 18:51). |
| AMA | ETUN. Acronym Geek. February 14, 2012, 18:51. Available at: http://www.acronymgeek.com/ETUN. Accessed February 14, 2012, 18:51. |