Otto cycle : The series of actions in the working of a four-stroke (ordinary kind of) motor car engine: (1) in-take of oil-vapour, (2) compress, (3) fire, (4) drive out burnt gases
H. J. Porter (Chairman - Technical Committee), Dictionary of Fire Technology, The Institution of Fire Engineers, The Victory Press (Leicester) Ltd. 1979 UK. (Fr Tech - Brit) {81}