| APA | SPN. (2012, February 9). In Acronym Geek. Retrieved 21:04, February 9, 2012, from http://www.acronymgeek.com/SPN |
| MLA | "SPN." Acronym Geek. (2012). Acronym Geek. 9 Feb 2012 <http://www.acronymgeek.com/SPN>. |
| MHRA | 'SPN', Acronym Geek, 9 February 2012, <http://www.acronymgeek.com/SPN> [accessed 9 February 2012] |
| Chicago | "SPN", http://www.acronymgeek.com/SPN (accessed February 9, 2012). |
| CBE/CSE | SPN [Internet]. Acronym Geek; 2012 Feb 9 [cited 2012 Feb 9]. Available from: http://www.acronymgeek.com/SPN. |
| Bluebook | SPN, http://www.acronymgeek.com/SPN (last visited February 9, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, SPN, http://www.acronymgeek.com/SPN (optional description here) (as of Feb. 9, 2012, 21:04). |
| AMA | SPN. Acronym Geek. February 9, 2012, 21:04. Available at: http://www.acronymgeek.com/SPN. Accessed February 9, 2012, 21:04. |