B. Velliyangiri, P. Boobalan, M. Devakumar, V. G. Dharamarajan, and S. Dhibahar. “Performance Analysis of Economizer Using Wrought Iron Tubes”. International Journal of Intellectual Advancements and Research in Engineering Computations, vol. 6, no. 1, Mar. 2018, pp. 430-4, https://ijiarec.com/ijiarec/article/view/480.