Frutiger, Adrian (1967-02-27). "The IBM Selectric Composer: The Evolution of Composition Technology". IBM Journal of Research and Development. 12 (1). IBM: 9–14. doi:10.1147/rd.121.0009.
"Ghostscript". Ghostscript. Retrieved 19 January 2015.
letterpress.ch
Boag, Andrew (2000). "Monotype and Phototypesetting"(PDF). Journal of the Printing History Society: 57–77. Archived from the original(PDF) on 28 March 2016. Retrieved 22 July 2016.
Boag, Andrew (2000). "Monotype and Phototypesetting"(PDF). Journal of the Printing History Society: 57–77. Archived from the original(PDF) on 28 March 2016. Retrieved 22 July 2016.