United States. Department of the Treasury. "Report on the Finances, December 1848," Annual Report of the Secretary of the Treasury on the State of the Finances (1848). https://fraser.stlouisfed.org/content/?item_id=5493&filepath=/files/docs/publications/treasar/AR_TREASURY_1848.pdf, accessed on July 23, 2018.
Extracted from Reports of the Secretary of the Treasury of the United States... Vol. VI