@article{GDZPPN001177192, title = {The Haar Condition and Multiplicity of Zeros.}, journal = {Numerische Mathematik}, volume = {39}, year = {1982}, pages = {139-154}, zbl = {0489.41028}, url = {http://dml.mathdoc.fr/item/GDZPPN001177192} }
Vel, H. van de. The Haar Condition and Multiplicity of Zeros.. Numerische Mathematik, Tome 39 (1982) pp. 139-154. http://gdmltest.u-ga.fr/item/GDZPPN001177192/