BTM Hollerith Mechanical Service Manual  c1947

BTM Hollerith Mechanical Service Manual  c1948

BTM Hollerith Collator 077 Illustrated Part List  c1945

BTM Hollerith Punching Reproducer Illustrated Part List  c1947

BTM Hollerith Semi-Auto Bill Feed Illustrated Part List  c1949

BTM Hollerith Carriage Universal Drive Illustrated Part List  c1949

BTM Hollerith Junior Rolling Total Drive Illustrated Part List  c1949

BTM Hollerith Tabulator Equipment Manuals & Papers  c1937 to 1952

Original Press Photo of the Psychology test Hollerith  c1932

BTM Hollerith System installed at Liverpool  c1959