1. “Ground state of excitons and charged excitons in a quantum well”. Riva C, Peeters FM, Varga K, Physica status solidi: A: applied researchT2 – 6th International Conference on Optics of Excitons in Confined Systems, (OECS-6), AUG 30-SEP 02, 1999, ASCONA, SWITZERLAND 178, 513 (2000).   http://doi.org/10.1002/1521-396X(200003)178:1<513::AID-PSSA513>3.0.CO;2-1