@article{10_4064_sm_96_3_263_275,
     author = {Waldemar Hebisch},
     title = {Almost everywhere summability of eigenfunction expansions associated to elliptic operators},
     journal = {Studia Mathematica},
     pages = {263--275},
     year = {1990},
     volume = {96},
     number = {3},
     doi = {10.4064/sm-96-3-263-275},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-96-3-263-275/}
}