Mumford, T. L. (1883). The Switerland of America: Historical sketch of the Switch Back Railroad, the discovery of anthracite coal, and an account of the rise and growth of the Lehigh Coal and Navigation Company. [New York: American Bank Note Co.].

Mumford, Theodore L. The Switerland of America: Historical Sketch of the Switch Back Railroad, the Discovery of Anthracite Coal, and an Account of the Rise and Growth of the Lehigh Coal and Navigation Company. [New York: American Bank Note Co.], 1883.

Mumford, Theodore L. The Switerland of America: Historical Sketch of the Switch Back Railroad, the Discovery of Anthracite Coal, and an Account of the Rise and Growth of the Lehigh Coal and Navigation Company. [New York: American Bank Note Co.], 1883.