Although Stanfield worked to try to unify the party, Diefenbaker and his loyalists proved difficult to reconcile. The division in the party broke out in well-publicised dissensions, as when Diefenbaker called on Progressive Conservative MPs to break with Stanfield's position on the Official Languages bill, and nearly half the caucus voted against their leader's will or abstained. In addition to his parliamentary activities, Diefenbaker travelled extensively and began work on his memoirs, which were published in three volumes between 1975 and 1977. Pearson died of cancer in 1972, and Diefenbaker was asked if he had kind words for his old rival. Diefenbaker shook his head and said only, "He shouldn't have won the Nobel Prize."