Locating cloud to ground lightning flashes with simultaneous two station measurements. D.U. J .Sonnadara, A. B. Weerasekara, I. M. K. Fernando, R. Lelwala, K. P. S. C. Jayaratne, T. R. Ariyaratne, S. Namasivayam, and K. R. A.B andara, Sri Lankan Journal of Physics-Vol 1 ( 2000-March) 1