U. P.  Lad, Kulkarni, M. A., Desai, U. V., and Wadgaonkar, P. P., ?Lithium tetrafluoroborate catalyzed highly efficient inter- and intramolecular aza-Michael addition with aromatic amines?, Comptes Rendus Chimie, vol. 14, no. 12, pp. 1059-1064, 2011.