simple up-down: is there an original reference?

[Massimo Grassi <massimo.grassi@xxxxxxxx>]

Dear list,

I always been told that von Békésy was the first to use (or the inventor 
of) the "simple up-down" staircase.

Is there a precise reference for it? I checked more than a dozen of 
articles by now, but everybody seems to sweep this problem under the 
rug. Perhaps because there is not such a reference?

m

--
Massimo Grassi - PhD
Dipartimento di Psicologia Generale
Via Venezia 8 - 35131 Padova - Italy
http://www.psy.unipd.it/~grassi
http://percezione.wordpress.com/