found: Polito, Ronald. A Dir. of Massachusetts Photographers, 1993:p. 365 (Bierstadt Brothers (Charles, Edward, & Albert); New Bedford, Mass. ca. 1860-1867; succeeded by Stephen F. Adams)
found: Johnson, William S. Nineteenth-Century Photography, 1990(Bierstadt Brothers (Albert, Charles, Edward); New Bedford, Mass.; act. New England area making & selling stereo views; ca. 1859-1867; 1867 sold gallery to S. F. Adams)
found: George Eastman House Photography Database, via Internet, Aug. 8, 2002(Bierstadt Bros.; ca. 1850s-1860s; succeeded by S.F. Adams in 1866)