Jagadesan, S. and Subramanian, M. V. (2016) “Study on Sunspots, Ozone and earth atmosphere variation at Pudukkottai, Tamilnadu (latitude: 100 23’ and longitude 780 52’)”, International Journal of Science and Engineering Invention, p. 205 to 212. doi: 10.23958/ijsei/vol02-i07/05.