1. Araújo, F. C., Mansur, W. J., and Malaghini, J. E. B., ‘Biconjugate Gradient Acceleration for Large BEM Systems of Equations’, BEM XII, Vol. 1, (Eds. Brebbia, C. A., and Honma, T. ), Computational Mechanics Publications/Springer Verlag, Berlin, 1990.
2. Axelsson, O., ‘Conjugate Gradient Type Methods for Unsymmetric and Inconsistent Systems of Linear Equations’, Lin. Alg. & Its Applic., Vol. 29, pp. 1 - 16, 1980.
3. Bettess, J. A., ‘Solution Techniques for Boundary Integral Matrices’, Chapter 7, Numerical Methods for Transient and Coupled Problems, (Eds. Lewis, R. W., Hinton, E., Bettess, P., and Schrefler, B. A.), pp. 123-146, John Wiley and Sons Ltd, Chichester and New York, 1987
4. Bettess, J. A., ‘Economical Solution Technique for Boundary Integral Matrices’, Int. J. Numer. Meth. Engng., Vol. 19, No. 7, pp. 1073 - 1077, 1983.
5. Brebbia, C. A., Telles, J. C. F., and Wrobel, L. C., ‘Potential Problems’, Chapter 2, Boundary Element Techniques, pp. 47-109, Springer-Verlag, Berlin, 1984.