Addendum to the paper “Numerical solution of second-order equations on plane domains”
ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Volume 27 (1993) no. 1, p. 1-7 
@article{M2AN_1993__27_1_1_0,
     author = {Angermann, L.},
     title = {Addendum to the paper ``Numerical solution of second-order equations on plane domains''},
     journal = {ESAIM: Mathematical Modelling and Numerical Analysis - Mod\'elisation Math\'ematique et Analyse Num\'erique},
     publisher = {Dunod},
     volume = {27},
     number = {1},
     year = {1993},
     pages = {1-7},
     zbl = {0769.65077},
     mrnumber = {1204625},
     language = {en},
     url = {http://www.numdam.org/item/M2AN_1993__27_1_1_0}
}

Angermann, L. Addendum to the paper “Numerical solution of second-order equations on plane domains”. ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Volume 27 (1993) no. 1, pp. 1-7. http://www.numdam.org/item/M2AN_1993__27_1_1_0/

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