The CBE and CSE citation styles are really the same. CBE was renamed CSE in the recent past. The Council of Science Editors (CSE) offers three systems of documentation. Make sure you check with your instructor to find out what she wants you to use.
In all three systems, a reference list at the end of the paper provides all the information your reader needs to track down your sources. In-text references in your sentences show your reader which sources support the claims and information of that sentence.