@article{10_4153_CMB_1994_083_5,
     author = {Wang, Feng-Yu},
     title = {Gradient {Estimates} on {Rd}},
     journal = {Canadian mathematical bulletin},
     pages = {560--570},
     year = {1994},
     volume = {37},
     number = {4},
     doi = {10.4153/CMB-1994-083-5},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1994-083-5/}
}