Article 6, Clause 2
Document 26
James Madison, Report on the Virginia Resolutions
Jan. 1800(See Amend. I [speech and press], no. 24 )
The Founders' Constitution
Volume 4, Article 6, Clause 2, Document 26
http://press-pubs.uchicago.edu/founders/documents/a6_2s26.html
The University of Chicago Press