I hadn't, although I've got an earlier version of the textbook it's quoting. (I've not met him, but understand Ted Houghton is probably immortal, his "Aerodynamics for Engineering Students" has been co-authored by Brock, Caruthers, Carpenter and I think in latest edition by somebody else.)
However, the Glauert method of using a vorticity distribution to model an aerofoil chordwise (which is also in his 1926 "Aerofoil and airscrew theory" which is wonderful reading if you can ever find a copy) is about chordwise distribution - what I'm trying to work out is what's meant by a spanwise "Glauert distribution".
Nice website however, thanks for flagging it up.
Cheers,
G