Proceedings of the 8th International Conference on Squeezed States and Uncertainty Relations ICSSUR' 2003, 9-13 June 2003, Puebla, Mexico Proceedings of the 8th International Conference on Squeezed States and Uncertainty Relations ICSSUR' 2003, 9-13 June 2003, Puebla, Mexico, H. Moya-Cessa, R. Jáuregui, S. Hacyan, and O. Castaños, pp.140-147, 2003