Thank you for your reply Magister_Lang. I agree that "Fenris" would be more of a proper way of spelling it. I used to believe that "Fenriz" was perhaps the German variation of the word, but considering that the Teutonics shared the same Norse mythology, they used Fenrir or Fenrisúlfr. So therefore, I think that Fenrisúlfr may be the German variation of the word already. Although it may indeed be a "insignificant variant in phonetic translation that could have come from any older reference book on mythology," as Svengali stated ( Thank you for your reply as well by the way), I am still curious to where it came from. I'd like to think that Anton had a reason to why he decided to spell it that way in the Satanic Bible. Anyways, thank you once again, and if you do find out or remember where you saw it spelled the same way, feel free to PM me with the answer as well.