[FOM] acceptable enumerations

[T.Forster at dpmms.cam.ac.uk]

... as in ``acceptable enumeration of p.r. functions'' or acceptable 
enumeration of r.e. sets''...

I am in the market for a decent and thorough explanation of this important 
notion. I am away from my books and am nowhere near a library, but i do 
have the internet. Can anyone point me towards an electronically available
text of this nature? Or perhaps supply such an analysis themselves?

         tf