[rahen]

To be pedantic, V0 actually refers to the PDP-7 UNIX released in 1969.

1971 saw the port to the PDP-11/20, which was released as UNIX-11 and soon after, V1 UNIX.

[fanf2]

The edition numbers refer to the manual pages more than the software, which in the early days was under continual development running on approximately one machine. It wasn’t released in 1971.

[kragen]

or 01969, though it did exist