Basic Form Title, Bill or Resolution Number, Number of Congress Cong., Number of Session Sess. (Year).
Example Equitable Health Care for Severe Mental Illnesses Act of 1993, S. 671, 103d Cong., 1st Sess. (1993).
TEXT CITATION
Basic Form House Bill or Senate Bill number (Year)
Examples Senate Bill 671 (1993) provided for treatment of severe mental illnesses. A proposed law (S. 671, 1993) provided for treatment of severe mental illnesses.
You might also consult the Congressional Citation Guide for examples of APA, MLA, Chicago and Bluebook styles.