| APA | BPEN. (2012, February 15). In Acronym Geek. Retrieved 21:22, February 15, 2012, from http://www.acronymgeek.com/BPEN |
| MLA | "BPEN." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/BPEN>. |
| MHRA | 'BPEN', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/BPEN> [accessed 15 February 2012] |
| Chicago | "BPEN", http://www.acronymgeek.com/BPEN (accessed February 15, 2012). |
| CBE/CSE | BPEN [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/BPEN. |
| Bluebook | BPEN, http://www.acronymgeek.com/BPEN (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, BPEN, http://www.acronymgeek.com/BPEN (optional description here) (as of Feb. 15, 2012, 21:22). |
| AMA | BPEN. Acronym Geek. February 15, 2012, 21:22. Available at: http://www.acronymgeek.com/BPEN. Accessed February 15, 2012, 21:22. |