@article{AUCMP_1974__15_1-2_a9,
     author = {Hertling, J.},
     title = {Multivariate approximation theory with $\Delta$-splines},
     journal = {Acta Universitatis Carolinae. Mathematica et Physica},
     pages = {39--41},
     publisher = {mathdoc},
     volume = {15},
     number = {1-2},
     year = {1974},
     mrnumber = {0398053},
     zbl = {0309.41009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AUCMP_1974__15_1-2_a9/}
}