The battle to feed humanity is over. In the 1970s, the world will undergo famines. Hundreds of millions of people are going to starve to death in spite of any crash programs embarked upon now. Population control is the only answer -- Paul Ehrlich - The Population Bomb (1968) Additionally, "Stand On Zanzibar" (1968) John Brunner (Science Fiction, Hugo Award winner)
Lest we not forget ... Soylent Green!