For your consideration this very old original GWR locomotive engineering book from England, UK. The book contains pull out technical diagrams.
Vintage Maine Central Railroad Rules Engineering Dept book
1950 Bonds Model Railway & Engineering Catalogue Book
British Rail Engineering Dispatch Book 1985–87 – BREL Stores Log History
1967 Chicago And North Western System Rules Of The Engineering Department Book
1936 GWR Engineering Caersws to Inspector Egerton Builth Wells Bridge Memo
Great Western Society Didcot GWR Railwayana Booklet Book - GWR Railway Booklets