etymology question

hi, all.

while searching google, i found an old forum discussion in which the guy from etymonline was a involved. i thought i'd found the answer to my question but, for some reason, his site won't download for me. thought someone here could help:

what is the etymology of "process"? i'm looking for a credible source, something i can cite, something preferably in print.

any thoughts?

thanks, in advance...
cbg