@article{ETNA_2014__41__a24,
     author = {G\"unnel, Andreas and Herzog, Roland and Sachs, Ekkehard},
     title = {A note on preconditioners and scalar products in {Krylov} subspace methods for self-adjoint problems in {Hilbert} space},
     journal = {Electronic transactions on numerical analysis},
     pages = {13--20},
     publisher = {mathdoc},
     volume = {41},
     year = {2014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ETNA_2014__41__a24/}
}