Tilberg, Frederick (1960). "Across the Potomac". Antietam National Battlefield Site Maryland Historical Handbook. National Park Service. Retrieved February 2, 2007.
"National Park System Birthdays". National Park Service History. National Park Service. April 13, 2006. Archived from the original on February 16, 2007. Retrieved February 2, 2007.
Tilberg, Frederick (1960). "Antietam National Battlefield Site and Cemetery". Antietam National Battlefield Site Maryland Historical Handbook. National Park Service. Archived from the original on February 6, 2007. Retrieved February 2, 2007.
Lee, Ronald F. (1973). "III. The First Battlefield Parks,1890–1899". The Origin and Evolution of the National Military Park Idea. National Park Service. Archived from the original on February 13, 2007. Retrieved February 2, 2007.
"1930's". NPS Chronological Timeline. National Park Service. May 19, 2006. Archived from the original on February 10, 2008. Retrieved February 2, 2007.
"National Park System Birthdays". National Park Service History. National Park Service. April 13, 2006. Archived from the original on February 16, 2007. Retrieved February 2, 2007.
Tilberg, Frederick (1960). "Antietam National Battlefield Site and Cemetery". Antietam National Battlefield Site Maryland Historical Handbook. National Park Service. Archived from the original on February 6, 2007. Retrieved February 2, 2007.
Lee, Ronald F. (1973). "III. The First Battlefield Parks,1890–1899". The Origin and Evolution of the National Military Park Idea. National Park Service. Archived from the original on February 13, 2007. Retrieved February 2, 2007.
"1930's". NPS Chronological Timeline. National Park Service. May 19, 2006. Archived from the original on February 10, 2008. Retrieved February 2, 2007.