@article{NUMA_1986__50_133173,
     author = {D. Braess and P. Peisker},
     title = {A {Conjugate} {Gradient} {Method} and a {Multigrid} {Algorithm} for {Morley'} s {Finite} {Element} {Approximation} of the {Biharmonic} {Equation.}},
     journal = {Numerische Mathematik},
     pages = {567--586},
     publisher = {mathdoc},
     volume = {50},
     year = {1986},
     zbl = {0595.65113},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1986__50_133173/}
}