@article{10_4153_CMB_1989_042_5,
     author = {Herron, David A. and Schiff, Joel L.},
     title = {Positive {Harmonic} {Functions} and {Complete} {Metrics}},
     journal = {Canadian mathematical bulletin},
     pages = {286--297},
     year = {1989},
     volume = {32},
     number = {3},
     doi = {10.4153/CMB-1989-042-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1989-042-5/}
}