Mastering Genealogical Proof - Kindle edition by Thomas W. Jones. Reference Kindle eBooks @ Amazon.com.
I haven't yet purchased this book, but it looks like it would be very helpful. I was reminded to consider it by a post that was made at Dear Myrtle's facebook and website. "Myrt" has a study group for this instructional book by Thomas W. Jones at her Google Hangout. I have added the book to my Wish List at Amazon.