In my preceding msg, I have given the address of the site where the 7 first volumes of the "Cahiers" are posted (under the heading "Seminaire Ehresmann"). However I have made a slight error (kindly indicated to me by Marco Grandis). The correct address is: http://www.numdam.org/numdam-bin/feuilleter?j=SE&sl=0 With all my best wishes to all Andree C. Ehresmann