| APA | PTBD. (2012, February 17). In Acronym Geek. Retrieved 04:53, February 17, 2012, from http://www.acronymgeek.com/PTBD |
| MLA | "PTBD." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/PTBD>. |
| MHRA | 'PTBD', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/PTBD> [accessed 17 February 2012] |
| Chicago | "PTBD", http://www.acronymgeek.com/PTBD (accessed February 17, 2012). |
| CBE/CSE | PTBD [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/PTBD. |
| Bluebook | PTBD, http://www.acronymgeek.com/PTBD (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PTBD, http://www.acronymgeek.com/PTBD (optional description here) (as of Feb. 17, 2012, 04:53). |
| AMA | PTBD. Acronym Geek. February 17, 2012, 04:53. Available at: http://www.acronymgeek.com/PTBD. Accessed February 17, 2012, 04:53. |