2x -- if you can find a copy of that book, it's old, but it's an excellent reference.
I don't own a copy of Kevin's book (been waiting for the 2nd edition to come out, since he has stated that the current one is now so outdated) or the Barkers', though I'd like to get both. Do either one of those discuss the use of ultrasound in breeding management? ... That's my big goal for next year at the very least.