You can get the reference citation for any item in the Discovery Service by clicking the Cite link in the Tools menu on the right side of the Detailed View.
Clicking the link will bring the citation up in all the major referencing formats (WMU uses APA).
You can export a single citation from the Detailed View or multiple citations from a folder. In the folder view you can select items individually, or Select All, as in the example below. Then click the Export link from the Tools menu on the right of the page
From there, choose your export format. Most Bibliographic Management tools -- Refworks, EndNote, Mendelay -- will import records in the BibText or RIS format, so if there is not a direct export to the tool of your choice, you can download in one of those formats and upload it into your tool.
As it happens, WMU has a university wide subscription to Easybib, so you can Export Records from the Discovery Service to Easybib in a single step.
(Note: Easybib authenticates with your WMU Gmail account. The first time you use it, you will be prompted to log in with your WMU email address and password. Easybib will create your account automatically. After that, Easybib will automatically log you into your account if you are logged into your email.