Calibration Method for Particulate Matter Low-Cost Sensors Used in Ambient Air Quality Monitoring and Research. - Janani Venkatraman Jagatha; André Klausnitzer; Miriam Chacón-Mateos; Bernd Laquai; Evert Nieuwkoop; Peter van der Mark; Ulrich Vogt; Christoph Schneider (Sensors, 2021)