Spatial analysis of chronic obstructive pulmonary disease and its risk factors in an urban area of Trivandrum, Kerala, India oleh Sethulekshmi Surendran, Ananth Mohan, Mathew Joseph Valamparampil, Sanjeev Nair, Sreekanth Karthikeyan Balakrishnan, Achu Asokan Laila, Rajesh Reghunath, Chinu Jose, Amjith Rajeevan, Prasannakumar Vasudevakaimal, Anish Tekkumkara Surendrannair, Zinia Thajudeen Nujum, Sara Varghese, Alladi Mohan