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On Sat, 29 Apr 1995 12:35:11 -0700 Wendy E. Betts said:

>I've never seen her GF flour mix sold as a mix, people usually mix it
>themselves--it's just rice flour, potato starch flour and tapioca flour.
>You can get those from Dietary Specialties among other places.

Ener-G sells it in five pound bags.  It's probably a little more expensive
than mixing (I've not figured it out) but to some, well worth the convenience.
LL