Examples of typical reproduction methods include&colon; diazo (blueline), electrostatic (xerographic), photographic, laser, and ink jet. As with digital photocopiers, laser printers employ a xerographic printing process. Drawings are now reproduced using plotters and large format xerographic copiers. A microfilm printer contains a xerographic copying process, like a photocopier. Haloid introduced the first commercial xerographic copier, the Xerox Model A, in 1949. HP LaserJet printers employ xerographic laser-marking engines sourced from the Japanese company Canon. Work led to the first commercial xerographic equipment, and to the formation of Xerox corporation. The 1385 was followed by the first automatic xerographic printer, the Copyflo, in 1955. Diazo prints remained in use until they were replaced by xerographic print processes. When Robert Gundlach joined, he discovered that much of their xerographic research was accident based. As the xerographic process evolved, line overlay was left behind. It built upon an earlier co-operation, Indian Xerographic Systems, formed in 1982. The physics of the xerographic process are discussed at length in a book.