I am adding files from another manager, which renames files to "title"-"author"-"index number"-"ISBN" (with "-" as delimiter).
(?P<title>.+)-(?P<author>[^_]+)-(?P<dummy>.+)-(?P<isbn>.+)
Since Calibre has no use for "index number", I just use a 'dummy' instead, so that I can add "title", "author" and "ISBN"... works fine for so far!
So in your case you could try:
(?P<dummy>.+)-(?P<title>.+)-(?P<author>[^_]+)
Good luck and please share if it works!
tom
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