This information is made available with thanks to Evi Nemeth, Garth Snyder, Scott Seebass, and Trent R. Hein .
From the second edition of UNIX System Administration Handbook , published in January, 1995 by Prentice Hall's PTR Division.
The Refence Card is available by FTP from
ftp.admin.com:/admin/refcard
in Postscript and is made up of
6 sections:
Common Command Examples
Sendmail Ruleset Order
Tokens Used In sendmail.cf
DNS Record Types
Suggested Hardware Vendors
Pinouts For Serial Connections
Controlling Running Processes
Useful Internet Sites