@article{NUMA_1989__54_3_133328,
     author = {W. Hackbusch and Z.P. Nowak},
     title = {On the {Fast} {Matrix} {Multiplication} in the {Boundary} {Element} {Method} by {Panel} {Clustering.}},
     journal = {Numerische Mathematik},
     pages = {463--492},
     publisher = {mathdoc},
     volume = {54},
     number = {3},
     year = {1989},
     zbl = {0641.65038},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1989__54_3_133328/}
}