| APA | DD4D. (2012, February 16). In Acronym Geek. Retrieved 01:55, February 16, 2012, from http://www.acronymgeek.com/DD4D |
| MLA | "DD4D." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/DD4D>. |
| MHRA | 'DD4D', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/DD4D> [accessed 16 February 2012] |
| Chicago | "DD4D", http://www.acronymgeek.com/DD4D (accessed February 16, 2012). |
| CBE/CSE | DD4D [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/DD4D. |
| Bluebook | DD4D, http://www.acronymgeek.com/DD4D (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, DD4D, http://www.acronymgeek.com/DD4D (optional description here) (as of Feb. 16, 2012, 01:55). |
| AMA | DD4D. Acronym Geek. February 16, 2012, 01:55. Available at: http://www.acronymgeek.com/DD4D. Accessed February 16, 2012, 01:55. |