Absolute acoustic band gap in coupled multilayer structures D. Bria, B. Djafari-Rouhani, A. Bousfia, E. H. El Boudouti and A. Nougaoui Europhys. Lett., 55 6 (2001) 841-846 Published online: 01 December 2003 DOI: 10.1209/epl/i2001-00357-4