As regards "internal links" I have repeatedly found them to break. It depends, I suppose, on how different browsers detect the base URL. But whatever the cause, trying to save a few characters in a link by leaving out the "http://www.mudcat.org/" part, just because you are linking to a page within the domain, is not a reliable strategy. I have found it to cause 404s routinely. I recommend putting the whole path in place for each link you make.

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