| APA | NNPC. (2012, February 11). In Acronym Geek. Retrieved 19:58, February 11, 2012, from http://www.acronymgeek.com/NNPC |
| MLA | "NNPC." Acronym Geek. (2012). Acronym Geek. 11 Feb 2012 <http://www.acronymgeek.com/NNPC>. |
| MHRA | 'NNPC', Acronym Geek, 11 February 2012, <http://www.acronymgeek.com/NNPC> [accessed 11 February 2012] |
| Chicago | "NNPC", http://www.acronymgeek.com/NNPC (accessed February 11, 2012). |
| CBE/CSE | NNPC [Internet]. Acronym Geek; 2012 Feb 11 [cited 2012 Feb 11]. Available from: http://www.acronymgeek.com/NNPC. |
| Bluebook | NNPC, http://www.acronymgeek.com/NNPC (last visited February 11, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, NNPC, http://www.acronymgeek.com/NNPC (optional description here) (as of Feb. 11, 2012, 19:58). |
| AMA | NNPC. Acronym Geek. February 11, 2012, 19:58. Available at: http://www.acronymgeek.com/NNPC. Accessed February 11, 2012, 19:58. |