Use the Congressional Publications database to locate additional legislative documents such as bills, laws, hearings, house and senate reports and CRS reports. All these types of documents can provide important information on your topic.
For help with citing government documents:
From Proquest: http://congressional.proquest.com:8090/gh_howtocite.html
From Indiana University Bloomington: http://libraries.iub.edu/guide-citing-us-government-publications
limit document type results on the right side before searching or within results
once in a document, notice the related News on the right
Example: epa and "ozone standard"