| APA | IOP. (2012, February 9). In Acronym Geek. Retrieved 19:26, February 9, 2012, from http://www.acronymgeek.com/IOP |
| MLA | "IOP." Acronym Geek. (2012). Acronym Geek. 9 Feb 2012 <http://www.acronymgeek.com/IOP>. |
| MHRA | 'IOP', Acronym Geek, 9 February 2012, <http://www.acronymgeek.com/IOP> [accessed 9 February 2012] |
| Chicago | "IOP", http://www.acronymgeek.com/IOP (accessed February 9, 2012). |
| CBE/CSE | IOP [Internet]. Acronym Geek; 2012 Feb 9 [cited 2012 Feb 9]. Available from: http://www.acronymgeek.com/IOP. |
| Bluebook | IOP, http://www.acronymgeek.com/IOP (last visited February 9, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, IOP, http://www.acronymgeek.com/IOP (optional description here) (as of Feb. 9, 2012, 19:26). |
| AMA | IOP. Acronym Geek. February 9, 2012, 19:26. Available at: http://www.acronymgeek.com/IOP. Accessed February 9, 2012, 19:26. |