A. A. Avetisyan, G. G. Tokmajyan, and L. V. Karapetyan, “THE SYNTHESE OF NEW DERIVATIVES OF UNSATURATED γ-LACTONES CONTAINING TETRAZOLE RING”, Proc. YSU B: Chem. Biol. Sci., vol. 38, no. 1 (203), pp. 76–79, Dec. 2003.