There's also an early work by Vagn Holmboe, the Little Overture (M.  89)
from 1936 (premiered in an alternate version for 2 soloists and strings
in 1939.) This is, I believe, currently unpublished, however...  Composers
who have written trios for this combination include Joseph Goodman (1918-)
(trio published by Associated Music Publishers in 1967), David Gompper
(1954-) (trio in the archives of the MidAmerican Center for Contemporary
Music, c 1989) and of course those that Karl Miller listed...  perhaps a
group could do for this repertoire what the Verdehr has tried to do for
the violin/clarinet/piano repertoire.  Who knows.

-Eric Schissel
http://www.lightlink.com/schissel
http://www.livejournal.com/~malver