What software is needed to create PDF files?  (To replace https://support.proquest.com/articledetail?id=kA11W000000TjL3SAK&key=software%20pdf&pcat=All__c&icat= )
 
Many tools are available to create PDF files.  Some of them create solid PDFs for professional use; many do not.

Most authors, though, shouldn’t require special software at all.  
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