Your assumptions regarding the web links are correct. Direct hyperlinks to articles would not be allowable without the consent of the copyright rightsholder. This is especially true of sites that are open to the public - password protected sites may provide a little more flexibility. In order to put direct hyperlinks to articles on their websites, faculty would have to have a letter from the rightsholder (usually the publisher) granting permission - our office can help with this if they choose to go this route.
If you simply provided a link to the publisher's home page, where a student/viewer could find the article on their own, I see no copyright issue. When linking, publishers prefer that you direct viewers to their home page (instead of directly to the article) if possible. The only problem that may arise from this approach is article availability, I know some older articles may not be available online and publishers may update and remove older articles from time to time.
Regarding linking to a pre-print, that would be fine if the faculty member holds copyright to the preprint. Depending upon their agreement with the publisher, all rights to the article (even in pre-print form) may have passed to the publisher upon publication. If that is the case, we would of course need the publishers consent.
I hope I've answered your questions - if not, just let me know. From past experience, I know that publishers are typically reluctant to allow material to be placed on websites that are open to the public that they do not control. However, because the authors are also the faculty requesting permission they may make exceptions - if you choose to have the articles displayed in this format.
Thanks for your query and let us know if we can be of further help, Dale
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