http://publications.europa.eu/resource/authority/language/ENG Raquel Trillo Zaragoza, Historic air quality sensor raw observations (2020-01) TRAFAIR-2020-103 This dataset provides primitive non-calibrated air quality observation data for every year and month. Universidad de Zaragoza 15/05/2020 http://zaguan.unizar.es/record/95726 http://zaguan.unizar.es/record/95726