Ioannis Saresberiensis episcopi Carnotensis Policratici sive De nugis curialium et vestigiis philosophorum libri VIII / recognovit et prolegomenis, apparatu critico, commentario, indicibus instruxit Clemens C.I. Webb. (OCLC #965502804)

I was a little puzzled when I saw the author’s name on the front of this reprint. “John”? Just John? (Did he sign up for the NAF first before any other Johns got there that he needed to be disambiguated from?)

The authorized form of the author’s name made this clear:

100 0_ ǂa John, ǂc of Salisbury, Bishop of Chartres, ǂd -1180.

This particular John (of Salisbury) was best known by his forename (rather than a surname), so his authorized access point in the name authority file is established that way as well. The first indicator (0) of this 100 field indicates that we have a forename type element here.