| APA | OBEI. (2012, February 15). In Acronym Geek. Retrieved 05:09, February 15, 2012, from http://www.acronymgeek.com/OBEI |
| MLA | "OBEI." Acronym Geek. (2012). Acronym Geek. 15 Feb 2012 <http://www.acronymgeek.com/OBEI>. |
| MHRA | 'OBEI', Acronym Geek, 15 February 2012, <http://www.acronymgeek.com/OBEI> [accessed 15 February 2012] |
| Chicago | "OBEI", http://www.acronymgeek.com/OBEI (accessed February 15, 2012). |
| CBE/CSE | OBEI [Internet]. Acronym Geek; 2012 Feb 15 [cited 2012 Feb 15]. Available from: http://www.acronymgeek.com/OBEI. |
| Bluebook | OBEI, http://www.acronymgeek.com/OBEI (last visited February 15, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, OBEI, http://www.acronymgeek.com/OBEI (optional description here) (as of Feb. 15, 2012, 05:09). |
| AMA | OBEI. Acronym Geek. February 15, 2012, 05:09. Available at: http://www.acronymgeek.com/OBEI. Accessed February 15, 2012, 05:09. |