[Zope] Non short-circuit or statement (listing multiple document categories)

What is the correct way to generate a list of documents of several types. I used the following statement, which only lists the documents of the first category matched. <dtml-in expr="objectValues('STX_Document') or objectValues('Page Template') or objectValues('DTML Document')" sort="bobobase_modification_time" reverse> So if there are no STX_Document's the Page Template's get listed, but not the DTML Documents. Regards, Frank