Environmental Monitoring of Methane with Quartz-Enhanced Photoacoustic Spectroscopy Exploiting an Electronic Hygrometer to Compensate the H2O Influence on the Sensor Signal. - Arianna Elefante; Giansergio Menduni; Hubert Rossmadl; Verena Mackowiak; Marilena Giglio; Angelo Sampaolo; Pietro Patimisco; Vittorio M. N. Passaro; Vincenzo Spagnolo (Sensors, 2020)