Influence of Al content on temperature dependence of excitonic transitions in quantum wells S. A. Lourenço, I. F.L. Dias, E. Laureto, J. L. Duarte, D. O. Toginho Filho, E. A. Meneses and J. R. Leite Eur. Phys. J. B, 21 1 (2001) 11-17 Published online: 15 May 2001 DOI: 10.1007/s100510170207