John Hart Ely, The Irrepressible Myth of Erie, 87 Harv. L. Rev. 693 (1974) (suggested by Steve Vladeck).
Henry M. Hart, Jr., The Power of Congress to Limit the Jurisdiction of Federal Courts: An Exercise in Dialectic, 66 Harv. L. Rev. 1362 (1953) (suggested by Steve Vladeck).
Daniel J. Meltzer, State Court Forfeitures of Federal Rights, 99 Harv. L. Rev. 1128 (1986) (suggested by Mike Domino).
Antonin Scalia, The Doctrine of Standing as an Essential Element of the Separation of Powers, 17 Suffolk U. L. Rev. 891 (1983) (suggested by Mike Domino).
William W. Van Alstyne, A Critical Guide to Ex Parte McCardle,15 Ariz. L. Rev. 229 (1973) (suggested by Steve Vladeck).
Federal Courts and Civil Rights Law Books
Richard H. Fallon, Jr., et al., The Federal Courts and the Federal System. (5th ed. 2003) (I know textbooks aren't the typical thing to list here but Hart & Wechsler's The Federal Courts and the Federal System has always seemed to me a major work in the field. One could argue that it pretty much created the field. Plus, it bears the imprimatur of so many great writers on the subject, not only the two original authors but also its current editors (Meltzer, Fallon, Shapiro; suggested by Dave).