1. JP Bunt (2001) Nine-page typed letter, sent to Simon Lavington on 11 Dec 2001
2. Direct Digital Control. 10-page Company brochure, published by Elliott Process Automation Ltd., describing Type 1 and Type 2 direct digital controllers and how these may be part of the ARCH equipment and architecture. Undated but probably 1964. (For the Instrument Society of America’s background to the DDC meeting, see [22] below)
3. Leon Bagrit (1964) Automation – an extension of man. 12-page typed paper including the comment ‘prepared for the Imperial Defence College,’ dated May 1964
4. Anon (1962) An introduction to system design using Minilog switching elements. A 16-page illustrated technical brochure published by Panellit Ltd., a company within the Elliott-Automation Group. Undated, but it can be inferred by the reference on page 10 of the brochure that the date is not earlier than 1962
5. Hersom SE (ed) (2001) information contained in a series of e-mails sent to Simon Lavington in 2001