@article{NUMA_1986__49_133112,
     author = {Ronald Cools and Ann Haegemans},
     title = {Optimal {Addition} of {Knots} to {Cubature} {Formulae} for {Planar} {Regions.}},
     journal = {Numerische Mathematik},
     pages = {269--274},
     publisher = {mathdoc},
     volume = {49},
     year = {1986},
     zbl = {0574.65014},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1986__49_133112/}
}