@article{McMahon2006,
author = {McMahon, J.M. and Pouget, E.R. and Tortu, S. },
title= {A guide for multilevel modeling of dyadic data with binary outcomes using SAS PROC nlmixed},
year = {2006},
doi = {10.1016/j.csda.2005.08.008},
journal = {Computational Statistics and Data Analysis},
volume = {50},
number = {12},
pages = {3663--3680},
}