| APA | PO2. (2012, February 13). In Acronym Geek. Retrieved 22:54, February 13, 2012, from http://www.acronymgeek.com/PO2 |
| MLA | "PO2." Acronym Geek. (2012). Acronym Geek. 13 Feb 2012 <http://www.acronymgeek.com/PO2>. |
| MHRA | 'PO2', Acronym Geek, 13 February 2012, <http://www.acronymgeek.com/PO2> [accessed 13 February 2012] |
| Chicago | "PO2", http://www.acronymgeek.com/PO2 (accessed February 13, 2012). |
| CBE/CSE | PO2 [Internet]. Acronym Geek; 2012 Feb 13 [cited 2012 Feb 13]. Available from: http://www.acronymgeek.com/PO2. |
| Bluebook | PO2, http://www.acronymgeek.com/PO2 (last visited February 13, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PO2, http://www.acronymgeek.com/PO2 (optional description here) (as of Feb. 13, 2012, 22:54). |
| AMA | PO2. Acronym Geek. February 13, 2012, 22:54. Available at: http://www.acronymgeek.com/PO2. Accessed February 13, 2012, 22:54. |