par Ivar Ekeland . Modular curves and the Eisenstein ideal / by B. Mazur . Algebraic k-theory and crystalline cohomology / by Spencer Bloch . Infinitesimal computations in topology / by Dennis Sullivan . A counterexample to the rigidity conjecture for polyhedra / by Robert Connelly. -- Insitut des Hautes Études Scientifiques, 1977. -- (Publications mathématiques ; no. 47).