PT - JOURNAL ARTICLE AU - Heikki O Koskela AU - Anne M Lätti TI - Sputum production in chronic cough increases the probability of asthma. A cross-sectional questionnaire study AID - 10.1183/23120541.00086-2021 DP - 2021 Jan 01 TA - ERJ Open Research PG - 00086-2021 4099 - http://openres.ersjournals.com/content/early/2021/03/18/23120541.00086-2021.short 4100 - http://openres.ersjournals.com/content/early/2021/03/18/23120541.00086-2021.full