@article{TSG_2011-2012__30__77_0,
     author = {Helmensdorfer, Sebastian and Topping, Peter},
     title = {The {Geometry} of {Differential} {Harnack} {Estimates}},
     journal = {S\'eminaire de th\'eorie spectrale et g\'eom\'etrie},
     pages = {77--89},
     publisher = {Institut Fourier},
     address = {Grenoble},
     volume = {30},
     year = {2011-2012},
     doi = {10.5802/tsg.291},
     language = {en},
     url = {http://archive.numdam.org/articles/10.5802/tsg.291/}
}