REN, W.; KRENZKE, T.; WEST, B.; CANTOR, D. An Evaluation of the quality of interviewer and virtual observations and their value for nonresponse bias reduction . Survey Research Methods, [S. l.], v. 16, n. 1, p. 97–131, 2022. DOI: 10.18148/srm/2022.v16i1.7767. Disponível em: https://ojs.ub.uni-konstanz.de/srm/article/view/7767. Acesso em: 4 feb. 2023.