I'm sure this is old news to some of you, but I just found these. There are a ton of free books available on Google Books, here are some related to chickens. They are all old books (copyrights have expired) and so they are a good resource of how chickens were raised before electricity was a common convenience. Of course, you can find more recent books for sale there as well, including BYC's Raising Chickems for Dummies, but the link below are all free books.
https://play.google.com/store/search?q=Chickens&c=books&price=1
https://play.google.com/store/search?q=Chickens&c=books&price=1