@article{Glick1980,
author = {Glick, P.C.  and Spanier, G.B.},
title= {Married and unmarried cohabitation in the United-States},
year = {1980},
doi = {10.2307/351930},
journal = {Journal of Marriage and the Family},
volume = {42},
number = {1},
pages = {19--30},
}