ERS technical standard: Global Lung Function Initiative reference values for exhaled nitric oxide fraction ( F ENO 50 ) - Högman, Marieann; Bowerman, Cole; Chavez, Luis; Dressel, Holger; Malinovschi, Andrei; Radtke, Thomas; Stanojevic, Sanja; Steenbruggen, Irene; Turner, Steve; Dinh-Xuan, Anh Tuan (The European respiratory journal, 2024)