S. S.  Palimkar, P. Kumar, H., Lahoti, R. J., and Srinivasan, K. V., ?Ligand-, copper-, and amine-free one-pot synthesis of 2-substituted indoles via Sonogashira coupling 5-endo-dig cyclization?, Tetrahedron, vol. 62, no. 21, pp. 5109-5115, 2006.

K.  Venkatesan, Pujari, S. S., Lahoti, R. J., and Srinivasan, K. V., ?Efficient synthesis of 1,8-dioxo-octahydro-xanthene derivatives promoted by a room temperature ionic liquid at ambient conditions under ultrasound irradiation?, Ultrasonics Sonochemistry, vol. 15, no. 4, pp. 548-553, 2008.