Please prove that Linus was even a Bishop.
there is NO requirement that a Pope must be a bishop first, what makes you think that he must?
Please prove that Linus was even a Bishop.
Not much is known about Linus, and even less about Cletus, or Anacletus. I am sure you know more about it than I do. While I cannot attest to its validity, Wikipedia identifies several sources with references at this link:
http://en.wikipedia.org/wiki/Pope_Linus#cite_ref-kirsch_1-0
I have no idea how anyone would know what he looked like.