url update for Asperti & Longo: "Categories, Types and Structures"

Hi Frank, Thanks for making <http://www.cs.uu.nl/people/franka/ref.html>. Good idea! "Frank Atanassow" <franka@cs.uu.nl> writes:

[1] Andrea Asperti and Giussepe Longo. Categories, Types and Structures. An introduction to Category Theory for the working computer scientist. MIT Press, 1991. URL: http://www.dmi.ens.fr/users/longo/download.html

It seems ENS's DMI bifurcated... the current url is now http://www.di.ens.fr/users/longo/download.html Maybe you could update the link on your page too. Thanks, Jens