Thank you all. Many different approaches have been shared that work for the authors, so here is mine. I ignore the dogs and they go away. I have never been bitten or truly threatened. About the closest a dog has ever gotten is 2 feet. That seems threatening, I know, but not really in my "personal space" while out on the road. But some folks I ride with shout and scream at dogs and the dogs' behavior gets worse, louder, closer, more volatile and lasts longer.
In lieu of any published research we Bike Forum members will have to accept the anecdotal evident shared by other members and continue to make our own decisions on how to best handle dog interactions while riding. Enjoy!