John Stilwell Jenkins, Andrew Jackson (2011). “Life and Public Services of Gen. Andrew Jackson, Seventh President of the United States: Including the Most Important of His State Papers”, p.366, New Leaf Publishing Group
Florence Nightingale, Lynn McDonald (2004). “Florence Nightingale on Public Health Care: Collected Works of Florence Nightingale”, p.291, Wilfrid Laurier Univ. Press