Texas Retriever Trainer
Finished Dog by Charles Jurney
Training the Hunting Retriever by Bill Tarrant
Water Dog by Richard Wolters
Training Your Retriever by James Lamb Free
Smartwork for Retrievers I & II by Evan Graham
Tri-Tronics Retriever Training by Jim and Phyllis Dobbs
In addition to these, I have studied the Total Retriever Training videos featuring Mike Lardy,
and Hunting Retriever Puppy Training with John Amico.