Đọc thêm Thẻ bấm lỗ

Austrian, Geoffrey D. (1982). Herman Hollerith: The Forgotten Giant of Information Processing. Columbia University Press. tr. 418. ISBN 0-231-05146-8.
Cemach, Harry P. (1951). The Elements of Punched Card Accounting. Sir Issac Pitman & Sons Ltd. tr. 137. Machine illustrations were provided by Power-Samas Accounting Machines and British Tabulating Machine Co.
Fierheller, George A. (2006). Do not fold, spindle or mutilate: the "hole" story of punched cards (PDF). Stewart Pub. ISBN 1-894183-86-X. Truy cập ngày 3 tháng 4 năm 2018. An accessible book of recollections (sometimes with errors), with photographs and descriptions of many unit record machines.
Bản mẫu:Cite film An account of how IBM Cards are manufactured, with special emphasis on quality control.[1]
Lubar, Steve (tháng 5 năm 1991). “Do not fold, spindle or mutilate: A cultural history of the punch card”. Bản gốc lưu trữ ngày 30 tháng 8 năm 2006.
Murray, Francis J. (1961). Mathematical Machines Volume 1: Digital Computers, Chapter 6 Punched Cards. Columbia University Press. Includes a description of Samas punched cards and illustration of an Underwood Samas punched card.
Truedsell, Leon E. (1965). The Development of Punch Card Tabulation in the Bureau of the Census 1890-1940. US GPO. Includes extensive, detailed, description of Hollerith's first machines and their use for the 1890 census.

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