These old Gerrie Brown books are great reading. Full of useful information without any ads or B.S.. Upper left book page 90 has a picture of Steve and Donna Bobb (yikes!) as hosts of the 1974 Hershey National. Page 116 has a handwritten letter with picture of Ray Klingensmith as a teenager (double yikes) !! Bottom book has diagrams and pictures. Great addition for any mud collector. Both Gerald Brown books are signed. Upper right Knowles/Prism book was made in the gazillions as is pretty easy to find at shows. Large drawings/pictures with basic information on the manufacturer. Take all three for $10.00 + cheap media shipping. First email that says' "I'll take it.". No PayPal. Email with questions.