| APA | PBL. (2012, February 9). In Acronym Geek. Retrieved 20:24, February 9, 2012, from http://www.acronymgeek.com/PBL |
| MLA | "PBL." Acronym Geek. (2012). Acronym Geek. 9 Feb 2012 <http://www.acronymgeek.com/PBL>. |
| MHRA | 'PBL', Acronym Geek, 9 February 2012, <http://www.acronymgeek.com/PBL> [accessed 9 February 2012] |
| Chicago | "PBL", http://www.acronymgeek.com/PBL (accessed February 9, 2012). |
| CBE/CSE | PBL [Internet]. Acronym Geek; 2012 Feb 9 [cited 2012 Feb 9]. Available from: http://www.acronymgeek.com/PBL. |
| Bluebook | PBL, http://www.acronymgeek.com/PBL (last visited February 9, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PBL, http://www.acronymgeek.com/PBL (optional description here) (as of Feb. 9, 2012, 20:24). |
| AMA | PBL. Acronym Geek. February 9, 2012, 20:24. Available at: http://www.acronymgeek.com/PBL. Accessed February 9, 2012, 20:24. |