For citations:
Sergeeva G.R., Emel'yanov A.V., Leshenkova E.V., Znakhurenko A.A., Asatiani N.Z., Rumyantsev A.Sh. Fixed airflow obstruction in patients with asthma. PULMONOLOGIYA. 2020;30(3):295-304. (In Russ.) https://doi.org/10.18093/0869-0189-2020-30-3-295-304