@techreport{Kennedy2016,
author = {Kennedy, C. and Mercer, A. and Keeter, S. and Hatley, N. and McGeeney, K. and Gimenez, A.},
title= {Evaluating online nonprobability surveys},
year = {2016},
URL = {https://www.pewresearch.org/methods/2016/05/02/evaluating-online-nonprobability-surveys/},
}