J. M. Anto, P. Vermeire, J. Vestbo, et al., “Epidemiology of Chronic Obstructive Pulmonary Disease,” European Respiratory Journal, Vol. 17, No. 5, 2001, pp. 982-994. doi:10.1183/09031936.01.17509820
 S. Shohaimi, A. Welch, S. Bingham, et al., “Area Deprivation Predicts Lung Function Independently of Education and Social Class,” European Respiratory Journal, Vol. 24, No. 1, 2004, pp. 157-161. doi:10.1183/09031936.04.00088303
 D. A. Lawlor, S. Ebrahim and S. G. Davey, “Association between Self-Reported Childhood Socioeconomic Position and Adult Lung Function: Findings from the British Women’s Heart and Health Study,” Thorax, Vol. 59, No. 3, 2004, pp. 199-203. doi:10.1136/thorax.2003.008482
 J. E. Gern, L. A. Rosenthal, R. L. Sorkness and R. F. Lemanske Jr., “Effects of Viral Respiratory Infections on Lung Development and Childhood Asthma,” Journal of Allergy and Clinical Immunology, Vol. 115, No. 4, 2005, pp. 668-674. doi:10.1016/j.jaci.2005.01.057
 N. Bruce, R. Perez-Padilla and R. Albalak, “Indoor Air Pollution in Developing Countries: A Major Environmental and Public Health challenge,” Bulletin of the World Health Organization, Vol. 78, No. 9, 2000, pp. 1078-1092.
 P. Kulshreshtha, M. Khare and P. Seetharaman, “Indoor Air Quality Assessment in and around Urban Slums of Delhi City, India,” Indoor Air, Vol. 18, No. 6, 2008, pp. 488-498. doi:10.1111/j.1600-0668.2008.00550.x
 B. Brunekreef, R. Beelen, G. Hoek, et al., “Effects of Long-Term Exposure to Traffic-Related Air Pollution on Respiratory and Cardiovascular Mortality in the Netherlands: The NLCS-AIR Study,” Research Report (Health Effects Institute), Vol. 139, 2009, pp. 5-71, 73-89.
 A. L. Kozyrskyj, G. E. Kendall, P. Jacoby, et al., “Association between Socioeconomic Status and the Development of Asthma: Analyses of Income Trajectories,” American Journal of Public Health, Vol. 100, No. 3, 2010, pp. 540-546. doi:10.2105/AJPH.2008.150771
 S. Sen, J. Hobson and P. Joshi, “The Pune Slum Census: Creating a Socio-Economic and Spatial Information Base on a GIS for Integrated and Inclusive City Development,” Habitat International, Vol. 27, No. 4, 2003, pp. 595-611. doi:10.1016/S0197-3975(03)00007-9
 P. G. Burney, L. A. Laitinen, S. Perdrizet, et al., “Validity and Repeatability of the IUATLD (1984) Bronchial Symptoms Questionnaire: An International Comparison,” European Respiratory Journal, Vol. 2, No. 10, 1989, pp. 940-945.
 R. V. Chowgule, V. M. Shetye, J. R. Parmar, et al., “Prevalence of Respiratory Symptoms, Bronchial Hyperreactivity, and Asthma in a Mega city. Results of the European Community Respiratory Health Survey in Mumbai (Bombay),” American Journal of Respiratory and Critical Care Medicine, Vol. 158, 1998, pp. 547-554.
 A. N. Aggarwal, K. Chaudhry, S. K. Chhabra, et al., “Prevalence and Risk Factors for Bronchial Asthma in Indian Adults: A Multi-Centre Study,” Indian Journal of Chest Disease and Allied Sciences, Vol. 48, 2006, pp. 13-22.
 S. K. Jindal, A. N. Aggarwal, K. Chaudhry, et al., “Asthma Epidemiology Study Group. A Multicentric Study on Epidemiology of Chronic Obstructive Pulmonary Disease and Its Relationship with Tobacco Smoking and Environmental Tobacco Smoke Exposure,” Indian Journal of Chest Disease and Allied Sciences, Vol. 48, 2006, pp. 23-27.
 P. A. Mahesh, B. S. Jayraj, S. T. Prahlad, et al., “Validation of Structured Questionnaire for COPD and Prevalence of COPD in Rural Area of Mysore: A Pilot Study,” Lung India, Vol. 26, No. 3, 2009, pp. 63-69. doi:10.4103/0970-2113.53226
 A. Banerjee, J. S. Bhawalkar, S. L. Jadhav, et al., “Access to Health Services among Slum Dwellers in an Industrial Township and Surrounding Rural Areas: A Rapid Epidemiological Assessment,” Journal of Family Medicine and Primary Care, Vol. 1, No. 1, 2012, pp. 20-26.
 G. J. Huchon, A. Vergnenegre, F. Neukirch, et al., “Chronic Bronchitis among French Adults: High Prevalence and under Diagnosis,” European Respiratory Journal, Vol. 20, 2002, pp. 806-812. doi:10.1183/09031936.02.00042002
 R. E. Kanner, N. R. Anthonisen and J. E. Connett, “Lower Respiratory Illnesses Promote FEV1 Decline in Current Smokers But Not Ex-Smokers with Mild Chronic Obstructive Pulmonary Disease: Results from the Lung Health Study,” American Journal of Respiratory and Critical Care Medicine, Vol. 164, 2001, pp. 358-364.
 M. Masoli, D. Fabian, S. Holt, et al., “Global Initiative for Asthma (GINA) program: The Global Burden of Asthma: Executive Summary of the GINA Dissemination Committee Report,” Allergy, Vol. 59, 2004, pp. 469-478. doi:10.1111/j.1398-9995.2004.00526.x
 R. A. Pauwels, A. S. Buist, P. M. Calverley, et al., “The GOLD Scientific Committee. Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease. NHLBI/ WHO Global Initiative for Chronic Obstructive Lung Disease (GOLD) Workshop Summary,” American Journal of Respiratory and Critical Care Medicine, Vol. 163, 2001, pp. 12561276.
 L. E. Loschmann, J. Sunyer, E. Plana, et al., “Socioeconomic Status, Asthma and Chronic Bronchitis in a Large Community-Based Study,” European Respiratory Journal, Vol. 29, 2007, pp. 897-905. doi:10.1183/09031936.00101606
 S. Liu, Y. Zhou, X. Wang, et al., “Biomass Fuels Are the Probable Risk Factor for Chronic Obstructive Pulmonary Disease in Rural South China,” Thorax, Vol. 62, No. 10, 2007, pp. 889-897. doi:10.1136/thx.2006.061457
 S. O. Shaheen, D. J. P. Barker and S. T. Holgate, “Do Lower Respiratory Tract Infections in Early Childhood Cause Chronic Obstructive Pulmonary Disease?” American Journal of Critical Care Medicine, Vol. 151, No. 5, 1995, pp. 1649-1652.
 N. Kawakami, E. A. Abdulghani, J. Alonso, et al., “Early-Life Mental Disorders and Adult Household Income in the World Mental Health Surveys,” Biological Psychiatry, Vol. 72, No. 3, 2012, pp. 228-237. doi:10.1016/j.biopsych.2012.03.009