Books_that_refer_to_LEO

Lavington, Simon H. (1980) ‘Early British Computers: The Story of Vintage Computers and The People Who Built Them’, Manchester University Press, http://ed-thelen.org/comp-hist/EarlyBritish.html#TOC
Chapter 13, pages 68-77, gives a brief history of LEO and English Electric, including a timeline.

Lavington, Simon, (2011), Moving Targets: Elliott-Automation and the Dawn of the Computer Age 1947 – 67, Computer History, Springer. Although the book is primarily a history of Elliott-Automation it has a number of references to Lyons and LEO. See Google Books

Lavington, Simon (ed.) (2012) ‘Alan Turing and his Contemporaries’, British Computer Society. 111 pages, summarises the background to all the early British stored-program projects from 1945 – 1951. See Amazon

Lavington, S., (2019) Early Computing in Britain, Ferranti Ltd. and Government Funding, 1948 — 1958, Springer Computer History Series. A valuable addition to the exposure UK computing developments in the early years of computers with a focus on the initiatives taken by the Ferranti Company, in particular with their Mark I. LEO is only referred to in Appendix D, see https://www.springer.com/gp/book/9783030151027

Lean, T, (2016), Electronic Dreams: How 1980s Britain learned to love the computer, Bloomsberry/Sigma. The book includes references to LEO and its early success. Further References or Buy

Marshall, Stephen (2015) ‘The Story of the Computer: A Technical and Business History’, Kindle edition available. 592 pages the story of computing up to, but not including, the advent of smart phones. The LEO project is noted in Chapter 6, pages 198-189 and further mentions are made elsewhere such as the donation to EDSAC (Chapter 5, page 185). Reviewed by Dik Leatherdale in Resurrection Issue Number 79 Autumn 2017. Further References or Buy

Mathews, S., (2007), From Agit-Prop to Free Space: The Architecture of Cedric Price, Black Dog Publishing, London, U.K., 2007. 285 pp. Cedric Price a “visionary” architect: one whose schemes were grand was hired by Lyons to propose a radical redesign of one of its Corner Houses. In practice Lyons decided that they could not afford the re-design. The book makes a number of references to LEO including photos of a LEO installation. See More

MOD Secrets of Eastcote Government Office Site: The Customs Excise Years. 
(In 1947, under the inspiration of TR Thompson, Lyons, the firm of tea-shops, started – with remarkable foresight – to take a  serious  interest  in applying digital  computing to their accounting and office work generally.   By 1954, LEO (Lyons Electrical Office) computers carried out 3 commercial jobs  for  Lyons  –  the  bakeries’  payroll,  calculation  of production and schedule dispatch to 150 tea shops, and  the provision of management information.)
The the earlier Elliot 405 was replaced in 1963 by the tenth LEO 3 ever built. It  was  housed  in  H  Bay  (thought  by  many  to  have  been originally intended as the location for the Operating Theatre had D-Day proved more widely injurious), and, being a very advanced and powerful machine for its time, it aroused so much interest that a glass wall was built around it to allow for a viewing gallery. Data input was via Hollerith punched cards (rectangular holes, and 80 columns), and paper tape.  At this stage the purpose of the site’s computing power was purely for Census Office work, but later the Department’s Payroll system was computerised and run on the LEO, a huge undertaking. The LEO worked until 1971

Franco Angelstoryi, pp. 341-44 se

Springer, London. Chapter 3, ‘Early Computers’, provides a brief account of EDSAC and LEO. See more on Google Books