| APA | BTDU. (2012, February 15). In Acronym Geek. Retrieved 19:11, February 15, 2012, from http://www.acronymgeek.com/BTDU |
| MLA | "BTDU." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/BTDU>. |
| MHRA | 'BTDU', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/BTDU> [accessed 15 February 2012] |
| Chicago | "BTDU", http://www.acronymgeek.com/BTDU (accessed February 15, 2012). |
| CBE/CSE | BTDU [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/BTDU. |
| Bluebook | BTDU, http://www.acronymgeek.com/BTDU (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, BTDU, http://www.acronymgeek.com/BTDU (optional description here) (as of Feb. 15, 2012, 19:11). |
| AMA | BTDU. Acronym Geek. February 15, 2012, 19:11. Available at: http://www.acronymgeek.com/BTDU. Accessed February 15, 2012, 19:11. |