regexp(7g) on Linux
The text 49a6bcf265c7, as Debian 5.0 (Lenny), Debian 4.0 (Etch), Debian 3.1 (Sarge), Debian 3.0 (Woody), Debian 2.2 (Potato), Debian 2.1 (Slink), Debian 2.0 (Hamm) shipped it. The page shows this text now.
regular expression notation