The book "Predictably Irrational" by behavioral economist Dan Ariely that was mentioned early on in the article is also a good read. It does not directly related to pricing strategy but provide good insight to the irrational decisions that we make, and the BOGO falls into that category.

In a similar vein, I have just finished "Nudge: Improving Decisions About Health, Wealth, and Happiness" by Thaler and Sustein. This might be worth a look as well.