Baseball umpire mechanics and situations manual, spiral bound and three hole punched (for future binder use). Some changes in how we do things now - recommend [b:WOA Baseball Umpiring Mechanics Illustrated: 2 and 3 Person Crews|17344373|WOA Baseball Umpiring Mechanics Illustrated 2 and 3 Person Crews|Todd Stordahl|https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/books/1360460591l/17344373.SY75.jpg|24083034] instead for the latest mechanics - though it's not as easy to lie flat.

Volume II covers communication, a slim chapter in the newer book, and volume III covers 3- and 4-man mechanics. Mark Ambrosius' diagrams were trademarked in 1999 as "Mechanigrams" by Referee Magazine, the folks who published this also.