Wright Jr., Robert K.; MacGregor Jr., Morris J. (1987). "Soldier-Statesmen of the Constitution". Army historical series. Washington, D.C.: Center of Military History, United States Army. pp. 33–45. Archived from the original on October 9, 2019. Retrieved March 3, 2014.
Wright Jr., Robert K.; MacGregor Jr., Morris J. (1987). "Soldier-Statesmen of the Constitution". Army historical series. Washington, D.C.: Center of Military History, United States Army. pp. 33–45. Archived from the original on October 9, 2019. Retrieved March 3, 2014.
Spaulding, Matthew. "Attestation Clause". The Heritage Foundation. Archived from the original on April 21, 2012. Retrieved July 16, 2016.