| Style | Reference Text |
|---|
| APA | HCO. (2009, January 9). In All Acronyms. Retrieved 16:41, January 9, 2009, from http://www.all-acronyms.com/HCO |
| MLA | "HCO." All Acronyms. 9 Jan 2009, 16:41. All Acronyms. 9 Jan 2009 <http://www.all-acronyms.com/HCO>. |
| MHRA | 'HCO', All Acronyms, 9 January 2009, 16:41, <http://www.all-acronyms.com/HCO> [accessed 9 January 2009] |
| Chicago | "HCO," http://www.all-acronyms.com/HCO (accessed January 9, 2009). |
| CBE/CSE | HCO [Internet]. All Acronyms; 2009 Jan 9, 16:41 [cited 2009 Jan 9]. Available from: http://www.all-acronyms.com/HCO. |
| Bluebook | HCO, http://www.all-acronyms.com/HCO (last visited January 9, 2009). |
| Bluebook: Harvard JOLT | See All Acronyms, HCO, http://www.all-acronyms.com/HCO (optional description here) (as of Jan. 9, 2009, 16:41). |
| AMA | HCO. All Acronyms. January 9, 2009, 16:41. Available at: http://www.all-acronyms.com/HCO. Accessed January 9, 2009. |
Harvard College Observatory