I know links to several of these articles have been shared on the forum before but I found a spot that has a number of them all in one place for easy access.

http://positively.com/positive-reinforcement/the-science-behind-the-philosophy/

P.S. Looks like Victoria Stilwell is expanding her "brand" out into training based on this website.

Thanks, i had not seen that page.

Here's one of my favorite links:

http://www.clickersolutions.com/articles/index.htm