From: jnc(a)mercury.lcs.mit.edu <mailto:jnc@mercury.lcs.mit.edu> (Noel Chiappa) Thanks for mentioning that; I'd never heard of it. Very interesting. A query: it seems to have been written with access to a set of manuals for the various early versions of Research Unix. The Unix Tree: http://minnie.tuhs.org/cgi-bin/utree.pl <http://minnie.tuhs.org/cgi-bin/utree.pl> has the manual pages for V3 and V4, and V6 and later, but not the other ones. Do the manuals used for the preparatio of that note still exist; and, if so, is there any chance of getting them scanned?