@article{JRAM_1990__404_153198,
     author = {A.M. Hinz and H. Kalf},
     title = {Subsoluton estimates and {Harnack's} inequality for {Schr\"odinger} operators.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {118--134},
     publisher = {mathdoc},
     volume = {404},
     year = {1990},
     zbl = {0779.35026},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1990__404_153198/}
}