Rinken, S., Domínguez-Álvarez, J.-A., Trujillo, M., Lafuente, R., Sotomayor, R. and Serrano-del-Rosal, R. (2020) “Combined mobile-phone and social-media sampling for web survey on social effects of COVID-19 in Spain”, Survey Research Methods, 14(2), pp. 165-170. doi: 10.18148/srm/2020.v14i2.7733.