Introducing the nilpotence theorem in stable homotopy theory:
Ethan Devinatz, Michael Hopkins, Jeffrey Smith, Nilpotence and Stable Homotopy Theory I, Annals of Mathematics Second Series, Vol. 128, No. 2 (Sep., 1988), pp. 207-241 (jstor:1971440)
Ethan Devinatz, Michael Hopkins, Jeffrey Smith, Nilpotence and Stable Homotopy Theory II, Annals of Mathematics Second Series, Vol. 148, No. 1 (Jul., 1998), pp. 1-49 (jstor:120991)