Which Unix version is installed?

I wanted to check the version in different Unices ( == UNIX’es).
Linux:
===================

>>cat /etc/issue
Red Hat Enterprise Linux ES release 4 (Nahant Update 6)
Kernel r on an m

>>cat /etc/*release
Red Hat Enterprise Linux ES release 4 (Nahant Update 6)

————————————————————-

Or (Red Hat):

>>cat /etc/redhat-release
Red Hat Enterprise Linux ES release 4 (Nahant Update 6)

Solaris:
===================
Like Linux:

>>cat /etc/*release
Solaris 10 5/08 s10s_u5wos_10 SPARC
Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
Use is subject to license terms.
Assembled 24 March 2008

AIX:
===================
http://www.unix.com/aix/64647-aix-version.html

——————————————————————————

>>oslevel -g
Fileset                                 Actual Level        Maintenance Level
—————————————————————————–
bos.rte                                 5.3.0.50            5.3.0.0

==================================================

References:
The forums on Whatsup.org.il :

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