| APA | PHBO. (2012, February 17). In Acronym Geek. Retrieved 07:05, February 17, 2012, from http://www.acronymgeek.com/PHBO |
| MLA | "PHBO." Acronym Geek. (2012). Acronym Geek. 17 Feb 2012 <http://www.acronymgeek.com/PHBO>. |
| MHRA | 'PHBO', Acronym Geek, 17 February 2012, <http://www.acronymgeek.com/PHBO> [accessed 17 February 2012] |
| Chicago | "PHBO", http://www.acronymgeek.com/PHBO (accessed February 17, 2012). |
| CBE/CSE | PHBO [Internet]. Acronym Geek; 2012 Feb 17 [cited 2012 Feb 17]. Available from: http://www.acronymgeek.com/PHBO. |
| Bluebook | PHBO, http://www.acronymgeek.com/PHBO (last visited February 17, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PHBO, http://www.acronymgeek.com/PHBO (optional description here) (as of Feb. 17, 2012, 07:05). |
| AMA | PHBO. Acronym Geek. February 17, 2012, 07:05. Available at: http://www.acronymgeek.com/PHBO. Accessed February 17, 2012, 07:05. |