@article{Schwartz2009,
author = {Schwartz, C.R. and Graf, N.L.},
title= {Assortative matching among same-sex and different-sex couples in the United States, 1990–2000},
year = {2009},
doi = {10.4054/DemRes.2009.21.28},
volume = {21},
number = {28},
pages = {843--878},
}