The cyclic groups and the free loop space. R.L. Cohen; G.E. Carlsson — 1987 Commentarii mathematici Helvetici
The homotopy type of rational functions. F.R. Cohen; R.L. Cohen; B.M. Mann — 1993 Mathematische Zeitschrift
The Kervaire invariant of immersions. M. Mahowald; R.L. Cohen; J.D.S. Jones — 1985 Inventiones mathematicae