That link is to the 1913 Catholic Encyclopedia. A new edition came out in 1967, and an inferior revision came out in 2002. Neither newer editions are yet online.
I've long wondered whether the translation of the 1913 Catholic Encyclopedia to the Internet via New Advent a generation ago was an inspiration for the translation to the Internet several years later of the famous 11th edition of the Encyclopedia Britannica (1910-11) as the core of what became Wikipedia.
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