@misc{Smith2015,
author = {Smith, T.W. and Marsden, P. and Hout, M. and Kim, J. },
title= {General social surveys, 1972–2014 [machine-readable data file]},
year = {2015},
URL = {http://gss.norc.org/get-the-data/stata},
publisher = {NORC},
address = {Chicago},
}