Re: Affect of prices
Bookbub is quite a handy site for finding these kinds of books (the Hayes book was featured recently) either free or heavily discounted:
https://www.bookbub.com/home/
(BTW, it's "effect", not "affect")
Bookbub is quite a handy site for finding these kinds of books (the Hayes book was featured recently) either free or heavily discounted:
https://www.bookbub.com/home/
(BTW, it's "effect", not "affect")