I'm seldom more than a couple feet from my Knuth, Second Printing 1969,
$19.50 at the Tech Coop.

On page 147, Knuth credits

The idea of local symbols was introduced by M. E. Conway in 1958, in
connection with an assembly program for the UNIVAC 1.


On Sun, Oct 20, 2019 at 9:41 AM Norman Wilson <norman@oclsc.org> wrote:

> In `UNIX Assembler Reference Manual,' Dennis credits Knuth
> for numeric temporary labels, with a reference to volume 1
> of The Art of Computer Programming.
>
> I'm several thousand kilometers from my copy of Knuth (though
> rather nearer to Knuth himself, albeit not within asking
> range), so I'll leave it to others to track down the exact
> reference.
>
> Norman Wilson
> Toronto ON
> (temporarily Sacramento CA)
>