@article{NUMA_1984__43_132904,
     author = {Rolf Rannacher},
     title = {Finite {Element} {Solution} of {Diffusion} {Problems} with {Irregular} {Data.}},
     journal = {Numerische Mathematik},
     pages = {309--328},
     publisher = {mathdoc},
     volume = {43},
     year = {1984},
     zbl = {0512.65082},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1984__43_132904/}
}