@article{10_21136_MB_1999_126254,
     author = {Heinig, Hans P.},
     title = {Modular inequalities for the {Hardy} averaging operator},
     journal = {Mathematica Bohemica},
     pages = {231--244},
     publisher = {mathdoc},
     volume = {124},
     number = {2-3},
     year = {1999},
     doi = {10.21136/MB.1999.126254},
     mrnumber = {1780694},
     zbl = {0936.26006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.1999.126254/}
}