I was especially looking for the original conference. It's not the idea but the context I'm interested in. As you said, for the ideas there are a lot of data around.

If you want context, I'd recommend reading books.

There's one in particular that has an excellent bibliography, and which I've cribbed from extensively: William Ophuls, Ecology and the Politics of Scarcity, published in 1977. I'm linking the 1992 update (which might be found online via LibGen or Bo-ok.org), which doesn't depart much from the original, does extend some observations, and should include the references of the former. Both books are based on Ophuls PhD thesis (political science, Yale), published ~1972.

In particular, Ophuls looks at much of the literature of the previous 25 years or so, both on the limits side and the cornucopians.

https://www.worldcat.org/title/ecology-and-the-politics-of-s...

You might in particular be interested in The Next Hundred Years, a view from 1950:

https://www.worldcat.org/title/next-hundred-years/oclc/12006...

Or Charles Galton Darwin's The Next Million Years. Yes, grandson of the other C.D., and with a ridiculously qualified biography of his own.

https://www.worldcat.org/title/next-million-years/oclc/14145...

Richard Meier's Science and Economic Development is also fairly mainstream:

https://www.worldcat.org/title/science-and-economic-developm...

Also noting: Ophuls explicitly supports the view of limits. But he does a very good job of treating both sides of the argument, particularly in his bibliography, and favours steelman rather than strawman opponents.