"Gutenberg" by User:Shizhao, User:Liberal Freemason - http://www.sru.edu/depts/cisba/compsci/dailey/217students/sgm8660/Final/. Licensed under Public domain via Wikimedia Commons.
"Printer in 1568-ce" by Jost Amman - Meggs, Philip B. A History of Graphic Design. John Wiley & Sons, Inc. 1998. (p 64). Licensed under Public domain via Wikimedia Commons.