UNIX release history

[Whoffman]

Hello,
   I am looking for information on the differences between the
various releases of the different versions of UNIX. To be more
specific what is the difference between AT&T version 2 and version 3,
version 4 etc. Similarly for the BSD versions. i.e what does buying
this
version give me in addition to the last. references to books or
documents would be helpful. Thanks in advance,
						Bill

rutgers!aramis!whoffman
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