For more information
For more information about PER
in general check our our website at
http://www.physics.umd.edu/perg/
For references to the articles in PER on optics
check out the AJP resource letter on PER
by McDermott and Redish (Oct. 99)
http://www.physics.umd.edu/rgroups/
ripe/papers/rlpre.pdf