3Leonardi GS, Houthuijs D, Nikiforov B, et al. Respiratory symptoms, bronchitis and asthma in children of central and eastern Europe. Eur Respir J,2002,20:890-898.
4Luyt DK, Burton PR, Simpson H. Epidemiological study of wheeze, doctor diagnosed asthma, and cough in preschool children in Leicestershire. Br Med J, 1993,306 : 1386-1390.
5Faniran AO, Peat JK, Woolcock AJ. Measuring persistent cough in children in epidemiological studies: development of a questionnaire and assessment of prevalence in two countries. Chest. 1999.115,434-439.
6Charlton A. Childrens coughs related to parental smoking. Br Med J , 1984,288 : 1647-1649.
7Shann F. How often do children cough? Lancet, 1996,348:699- 700.
8Chang AB. Cough: are children really different to adults? Cough, 2005,1:7.
9Morice AH, Fontana GA, Sovijarvi AR, et al. The diagnosis and management of chronic cough. Eur Respir J ,2004,24:481-492.
10Chang AB ,Glomb WB. Guidelines for evaluating chronic cough in pediatrics: ACCP evidence-based clinical practice guidelines. Chest, 2006, 129 ( 1 Suppl) :260-283.