Start with the names of the government, government agency and subdivision associated with the source material. Each item should be separated by a period. You can abbreviate "Congress" as "Cong." and use common acronyms like DOT (Department of Transportation) and EPA (Environmental Protection Agency). If your document was used in a Congressional Senate Committee on energy, then your citation should, so far, look like this:United States. Cong. Senate. Committee on Energy. On the off-chance that your document has a recognized author, his name should precede this information--in the order last name, first name--but does not need to include a title.
Follow this information with the title of the document, followed by a period. If your word processor supports italics, use them for the title. If it does not, use an underscore to indicate that the title should be underlined. For example, if the title of the document is "Alternative Fuel Options Available in Less than Six Months," then your citation should read:United States. Cong. Senate. Committee on Energy. _Alternative Fuel Options Available in Less than Six Months_.
Include the Congressional number and session. These should be separated by a comma and followed by a period. You can abbreviate the word "session" as "sess." If the document originated in the 109th Congress in the second session, your citation should appear this way:United States. Cong. Senate. Committee on Energy. _Alternative Fuel Options Available in Less than Six Months_. 109th Cong., 2nd sess.
Add the site of origination for the document, followed by a colon. For example, if the publication is part of a committee report that was formulated in Washington, D.C. you can write your citation like this:United States. Cong. Senate. Committee on Energy. _Alternative Fuel Options Available in Less than Six Months_. 109th Cong., 2nd sess. Washington:
Finish with the publisher and the year of publication. Generally, when you are citing U.S. government documents, the publisher will be the Government Printing Office, abbreviated GPO. This should be followed by a comma, the year and a period. So if your document is from 2000, your finished citation will look like this:United States. Cong. Senate. Committee on Energy. _Alternative Fuel Options Available in Less than Six Months_. 109th Cong., 2nd sess. Washington: GPO, 2000.