1. Drasdo, D., Hwa, T. and Lässig, M. A statistical theory of sequence alignment with gap. Proceedings of the 6th International Conference on Intelligent Systems for Molecular Biology. pp.52–58.
2. Liu, J. S. and Lawrence, C. E. Statistical models for multiple sequence alignment: unifications and generalizations. Proceedings of the American Statistical Association: Statistical Computing Section. pp.1–8.