@article{Poortman2012,
author = {Poortman, A. R. and Mills, M},
title= {Investments in marriage and cohabitation: The role of legal and interpersonal commitment},
year = {2012},
doi = {10.1111/j.1741-3737.2011.00954.x},
journal = {Journal of Marriage and Family },
volume = {74},
number = {2},
pages = {357--376},
}