author = { Lau, Yan National Bureau of Economic Research Rosen, Harvey S. },

title = { Are Universities Becoming More Unequal? },

publisher = {National Bureau of Economic Research},

year = {July 2015},

booktitle = {NBER working paper series ; no. w21432},

address = { Cambridge, Mass },

url = { http://slubdd.de/katalog?TN_libero_mab2 }