[Zope] List of object's name in a ZClass

Hi, In a Zope folder, I have : - 1 instance of a personnal ZClass A - 10 or more instances of ZClass B - a DTML document I would like to call a DTML method (which is implemented in the ZClass A) from the DTML document to display a list of all instances names of ZClasse B If somebody know how to do that... Thanks for all