Beef Cow Synchronization Protocols - these protocols are recommended by the North Central Region Bovine Reproduction Task Force

Estrus Synchronization: A Reproductive Management Tool - another valuable publication from Mel DeJarnette at Select Sires

Systematic Breeding Program for Dairy Cows - by Mike O'Connor at Penn State; describes advantages of systematic breeding programs, hormones used to synchronize heat and induce ovulation, commercial hormone products, estrous synchronization programs, and factors important to achieving success with synchronization programs

Estrus Synchronization Programs for Dairy Cows and Heifers (Dr. J.D. Olson)    

Estrus Synchronization Guide from Accelerated Genetics   

Handbook of Estrous Synchronization - written by Mike Day and Tom Geary and from the W-112 Regional Committee, this is an excellent 41-page description of estrous synchronization techniques.  it contains many figures and diagrams and an overview of reproductive processes to help understand the basis for estrous synchronization.