| Style | Reference Text |
|---|
| APA | 21C. (2012, May 16). In All Acronyms. Retrieved 20:42, May 16, 2012, from http://www.all-acronyms.com/21C |
| MLA | "21C." All Acronyms. 16 May 2012, 20:42. All Acronyms. 16 May 2012 <http://www.all-acronyms.com/21C>. |
| MHRA | '21C', All Acronyms, 16 May 2012, 20:42, <http://www.all-acronyms.com/21C> [accessed 16 May 2012] |
| Chicago | "21C," http://www.all-acronyms.com/21C (accessed May 16, 2012). |
| CBE/CSE | 21C [Internet]. All Acronyms; 2012 May 16, 20:42 [cited 2012 May 16]. Available from: http://www.all-acronyms.com/21C. |
| Bluebook | 21C, http://www.all-acronyms.com/21C (last visited May 16, 2012). |
| Bluebook: Harvard JOLT | See All Acronyms, 21C, http://www.all-acronyms.com/21C (optional description here) (as of May. 16, 2012, 20:42). |
| AMA | 21C. All Acronyms. May 16, 2012, 20:42. Available at: http://www.all-acronyms.com/21C. Accessed May 16, 2012. |
Second-in-Command