Oh wow! I've wanted a copy of “Efficient Linux at the Command Line” since I heard Daniel Barrett interviewed on @changelog (https://changelog.com/podcast/547) but it’s, like $30+ even for the eBook.
But there's a Humble Bundle with it in right now, along with a bunch of other Linux/bash/CLI books.
Really worth a look!
https://www.humblebundle.com/books/shells-and-scripting-for-seasoned-admins-oreilly-books