| APA | TDU. (2012, February 14). In Acronym Geek. Retrieved 19:24, February 14, 2012, from http://www.acronymgeek.com/TDU |
| MLA | "TDU." Acronym Geek. (2012). Acronym Geek. 14 Feb 2012 <http://www.acronymgeek.com/TDU>. |
| MHRA | 'TDU', Acronym Geek, 14 February 2012, <http://www.acronymgeek.com/TDU> [accessed 14 February 2012] |
| Chicago | "TDU", http://www.acronymgeek.com/TDU (accessed February 14, 2012). |
| CBE/CSE | TDU [Internet]. Acronym Geek; 2012 Feb 14 [cited 2012 Feb 14]. Available from: http://www.acronymgeek.com/TDU. |
| Bluebook | TDU, http://www.acronymgeek.com/TDU (last visited February 14, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, TDU, http://www.acronymgeek.com/TDU (optional description here) (as of Feb. 14, 2012, 19:24). |
| AMA | TDU. Acronym Geek. February 14, 2012, 19:24. Available at: http://www.acronymgeek.com/TDU. Accessed February 14, 2012, 19:24. |