| APA | PNAO. (2012, February 15). In Acronym Geek. Retrieved 05:28, February 15, 2012, from http://www.acronymgeek.com/PNAO |
| MLA | "PNAO." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/PNAO>. |
| MHRA | 'PNAO', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/PNAO> [accessed 15 February 2012] |
| Chicago | "PNAO", http://www.acronymgeek.com/PNAO (accessed February 15, 2012). |
| CBE/CSE | PNAO [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/PNAO. |
| Bluebook | PNAO, http://www.acronymgeek.com/PNAO (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, PNAO, http://www.acronymgeek.com/PNAO (optional description here) (as of Feb. 15, 2012, 05:28). |
| AMA | PNAO. Acronym Geek. February 15, 2012, 05:28. Available at: http://www.acronymgeek.com/PNAO. Accessed February 15, 2012, 05:28. |