He was re - elected in 1967 , 1971 , 1975 , 1977 and 1981 , and served as a backbencher in the John Robarts and William Davis governments .
Head entity: 1975 Q3586382 10
Tail entity: 1977 Q7094973 12
Relation (head \u2192 tail): P155
Inverse relation (tail \u2192 head): P156