Public domain
Dr. Cooley, one of the pioneers at the Rocky Mountain Laboratory in study of ticks and development of spotted fever vaccine. USPHS (United States Public Health Service) Laboratory, Hamilton, Montana
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineDr. Cooley, one of the pioneers at the Rocky Mountain Laboratory in study of ticks and development of spotted fever vaccine. USPHS (United States Public Health Service) Laboratory, Hamilton, Montana. 1942-01-01. Vachon, John. Farm Security Administration/Office of War Information Collection, Library of Congress. Public domain.