I had the same and as workaround downloaded the tar.gz and did what told on the page: Copy only the directory named "PloneArticle" inside the unpacked "Products.PloneArticle" directory Paste it to your zope instance Products dir.
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I had the same and as workaround downloaded the tar.gz and did what told on the page: Copy only the directory named "PloneArticle" inside the unpacked "Products.PloneArticle" directory Paste it to your zope instance Products dir.