1) Prof. P.C.Boole and Prof. C.S.Wallace invite A.P.Ershov to a cocktail party (16.10.1980). 2) Boarding pass of British airways for the route Singapore-London (19.10.1980). 3) Boarding pass of British airways (a form).

"A Grafted Multi-Access Network" by J.M.Bennett, C.S.Wallace, J.W.Winings.