RT Journal Article SR Electronic T1 Facemasks do not lead to abnormal gas exchange during treadmill exercise testing in children JF ERJ Open Research JO erjor FD European Respiratory Society SP 00613-2021 DO 10.1183/23120541.00613-2021 VO 8 IS 1 A1 Maria Christina Mallet A1 Michael Hitzler A1 Marco LurĂ  A1 Claudia E. Kuehni A1 Nicolas Regamey YR 2022 UL http://openres.ersjournals.com/content/8/1/00613-2021.abstract AB