[nickpsecurity]

Here's a great one from Pico project:

http://www.cl.cam.ac.uk/~fms27/papers/2012-BonneauHerOorSta-...

Other publications that might interest you:

http://pico.cl.cam.ac.uk/technical/

Ross Anderson's blog, LightBlueTouchpaper, has writeups on this in authentication category.