| APA | OOP. (2012, February 9). In Acronym Geek. Retrieved 19:43, February 9, 2012, from http://www.acronymgeek.com/OOP |
| MLA | "OOP." Acronym Geek. (2012). Acronym Geek. 9 Feb 2012 <http://www.acronymgeek.com/OOP>. |
| MHRA | 'OOP', Acronym Geek, 9 February 2012, <http://www.acronymgeek.com/OOP> [accessed 9 February 2012] |
| Chicago | "OOP", http://www.acronymgeek.com/OOP (accessed February 9, 2012). |
| CBE/CSE | OOP [Internet]. Acronym Geek; 2012 Feb 9 [cited 2012 Feb 9]. Available from: http://www.acronymgeek.com/OOP. |
| Bluebook | OOP, http://www.acronymgeek.com/OOP (last visited February 9, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OOP, http://www.acronymgeek.com/OOP (optional description here) (as of Feb. 9, 2012, 19:43). |
| AMA | OOP. Acronym Geek. February 9, 2012, 19:43. Available at: http://www.acronymgeek.com/OOP. Accessed February 9, 2012, 19:43. |