i don't know where the pdf's i find on the internet come from or if they're authorized (legal) or not. i don't know that the website for the Wagner pdf is the one that's 'authorized' or not.  (i do know that all 4 of my books can be found as free pdf's on the internet (not easily but they're there if you search long enough), even though i never acquiesed to it and some of them are still in print - though i get no royalties from any sales). i just wanted to give the most direct place to go to get pdf's without having to go through one of those e-book websites where you have to register - i avoid those places becuase of the possibilty of downloading a pdf that's not supposed to be available from a website that the NSA is monitoring - and they seem to monitor everything done by everyone. 

i'm just trying to help people access WL books. it's part of what i do as a self-appointed WL evangelist.

as for david wagner, he seems to have vanished. i only knew him in the 'old days' when he was an assistant professor somewhere.