[OT] Original citation for TDX

Gents and Ladies,

I'm looking for the original description of TDX. TDX, for those who don't
know, is a gravitationally polarized explosive that, instead of blowing up in
a big spherical blast wave, produces a shock wave along a thin plane
perpendicular to the ground. This is useful in sci-
fi for creating abatis, for clearing an emergency LZ for a VTOL in the forest,
etc. etc. Works pretty good for cutting enemy squads in half too.

What I'm wondering is.... who invented it? It was
some sci-fi author (I think maybe Alan Dean
Foster but I'm not sure) and what book was it first described in? I first
heard about it in an article for Traveller (the first game, not the subsequent
N incarnations) in White Dwarf a while before WD became a GW house organ. But
that wasn't its source.

Anyone who can help me, drop me an e-mail
off-list with any citation. I'd be interested to
locate the original work.

The original mention is from James Blish's Cities in Flight short story series
AKA the Okies.

Tony Finan - This is who we are.
"Let the revels begin, let the fire be started. We're dancing for the restless
and the broken hearted." This.sig terminates with Swan.
[quoted original message omitted]