| APA | NPOI. (2012, February 10). In Acronym Geek. Retrieved 08:03, February 10, 2012, from http://www.acronymgeek.com/NPOI |
| MLA | "NPOI." Acronym Geek. (2012). Acronym Geek. 10 Feb 2012 <http://www.acronymgeek.com/NPOI>. |
| MHRA | 'NPOI', Acronym Geek, 10 February 2012, <http://www.acronymgeek.com/NPOI> [accessed 10 February 2012] |
| Chicago | "NPOI", http://www.acronymgeek.com/NPOI (accessed February 10, 2012). |
| CBE/CSE | NPOI [Internet]. Acronym Geek; 2012 Feb 10 [cited 2012 Feb 10]. Available from: http://www.acronymgeek.com/NPOI. |
| Bluebook | NPOI, http://www.acronymgeek.com/NPOI (last visited February 10, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, NPOI, http://www.acronymgeek.com/NPOI (optional description here) (as of Feb. 10, 2012, 08:03). |
| AMA | NPOI. Acronym Geek. February 10, 2012, 08:03. Available at: http://www.acronymgeek.com/NPOI. Accessed February 10, 2012, 08:03. |