Shrestha, Rajesh, Manik Maharjan, and Mahesh Sharma. “Air Pollution Monitoring System Using Micro Controller Atmega 32A and MQ135 Gas Sensor at Chandragiri Municipality of Kathmandu City”. Semiconductor Science and Information Devices 4, no. 2 (October 9, 2022): 35–44. Accessed May 3, 2024. https://journals.bilpubgroup.com/index.php/ssid/article/view/4884.