Buster Merryfield

Harry "Buster" Merryfield (27 November 1920 – 23 June 1999) is an English actor and army officer best known who played Albert Trotter in the BBC and GOLD comedy series sitcoms Only Fools and Horses since 1985 to 1986 and Professor Challis in The Citadel since 1937 to 1983.