Context: I'm writing a dissertation in Computational Social Science using the Kluwer bibliographic style. My question isn't specific to this style and applies generally to dissertations in computer science, sociology, economics, and management.
Q: Should I include URL (DOI or other) in bibliographic entries for all journal or conference articles, in addition to normal full citation information?
There is no such requirement or guidelines from my University or Department. I've done numerous web searches, but I've never found any general guidelines on this.
Pro: All of my committee members and most of my readers now read articles on-line rather than through printed journals or proceedings. All the URLs will have hyperlinks, so when they are reading the PDF of my dissertation, they can click on the hyperlink that will open a browser window to the article. In addition, my dissertation will have internal hyperlinks from citations to bibliography entries and from key terms to glossary entries. Finally, I use the Zotero reference manager, and I can usually acquire the URL as part of the "one click" import process.
Con: Adding URLs for every journal/conference article adds visual clutter to the bibliography. When the URLs are not DOI, they may not be valid for a long time. It will add some work to test and correct URLs that don't meet the basic criteria of usability, consistency, and stability.