**CONTENTS**

*A. Bahri, J. M. Coron *Equation de Yamabe sur un ouvert non contractile

*Vieri Benci *A generalization of the Conley-index theory

*Marco Degiovanni, Antonio Marino *Bifurcation for some nonlinear elliptic variational inequalities

*Pavel Drábek *Systems of reaction-diffusion type with unilateral boundary conditions. The approach of M. Kučera

*Robert Gardner *Applications of the Conley index to reaction-diffusion systems

*Mario Girardi, Michele Matzeu *Solutions of minimal period for Hamiltonian systems with quadratic growth at the origin and superquadratic at infinity

*Krzysztof P. Rybakowski *Some recent results in the homotopy index theory in infinite dimensions

*Giovanna Cerami, Sergio Solimini *Multiplicity problems for elliptic equations with nonlinearities at critical growth

*Vittorio Coti Zelati *Solution of a BVP constrained in an infinitely deep potential well

*Pavel Drábek *Solvability of boundary value problems with homogeneous ordinary differential operator

*Jean Mittas, Stavros Ioulidis *Sur les hypergroupes polysymétriques commutatifs

*G. Morosanu, Dan Petrovanu *Nonlinear monotone boundary conditions for parabolic equations

*Alexander Abian *On the countability of a set of real numbers

*Bolis Basit *On a theorem of Gel’fand and a new proof of the Orlicz-Pettis theorem

*Krzysztof P. Rybakowski *On critical groups and the homotopy index in Morse theory on Hilbert manifolds

*János Körner, Andrea Sgarro *A new approach to rate-distortion theory

*Angelo Bella *On local T-tightness

*Carlo Greco *On forced oscillations of Lagrangian systems

*Roman Fric, Fabio Zanolin *Sequential convergence in free groups

** Editorial policy**
The journal *Rendiconti dell’Istituto di Matematica dell’università di Trieste * publishes original articles in all areas of mathematics. Special regard is given to research papers, but attractive expository papers may also be considered for publication.
The journal usually appears in one issue per year. Additional issues may however be published. In particular, the Managing Editors may consider the publication of supplementary volumes related to some special events, like conferences, workshops, and advanced schools.
All submitted papers will be refereed. Manuscripts are accepted for review with the understanding that the work has not been published before and is not under consideration for publication elsewhere.
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