there are 4 'Major sources" listed on the mail Ludlow family page, and 3 of them are defunct, though two of them can be found elsewhere. The Ludlow family history site no longer exists; I've written to Glenn Ludlow asking if there's a replacement. Of the 3 visitations sites listed, only the Shropshire one is findable as linked there (on internet archive), though the other two are also on the internet archive so can be fixed by updating the links. If you'd like me to do that I can.