The one that I posted is the one most commonly cited, and used. Whether it's the most accurate or right, almost is irrelevant. Because it's the formula most accepted (and listed by folks like Palmer and Papazian.) Therefore if you are brewing a recipe in a book or on a website, more than likely it was the formula the creator used to determine the abv for his recipe.
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Revvy's one of the cool reverends. He has a Harley and a t-shirt that says on the back "If you can read this, the bitch was Raptured. - Madman
I gotta tell ya, just between us girls, that Revvy is HOT. Very tall, gorgeous grey hair and a terrific smile. He's very good looking in person, with a charismatic personality... he drives like a ****ing maniac! - YooperBrew