@article{AM2_1971__7_136220,
     author = {R.J. HERBOLD and R.S. VARGA},
     title = {The {Effect} of {Quadrature} {Errors} in the {Numerical} {Solution} of {Two-Dimensional} {Boundary} {Value} {Problems} by {Variational} {Techniques}},
     journal = {Aequationes mathematicae},
     pages = {36--58},
     publisher = {mathdoc},
     volume = {7},
     year = {1971},
     zbl = {0233.65056},
     url = {http://geodesic.mathdoc.fr/item/AM2_1971__7_136220/}
}