Changes

* [http://byo.com/kegging/item/1691-sour-mashing-techniques Sour Mashing: Techniques, BYO, by Dave Green. October 2008.]

* [https://byo.com/videos/item/889-how-to-make-a-sour-mash-techniques How to Make a Sour Mash: Techniques, BYO, September 2000.]

=References=