@article{GT_2007_11_2_a5,
     author = {Lafont, Jean-Fran\c{c}ois and Schmidt, Benjamin},
     title = {Blocking light in compact {Riemannian} manifolds},
     journal = {Geometry & topology},
     pages = {867--887},
     publisher = {mathdoc},
     volume = {11},
     number = {2},
     year = {2007},
     doi = {10.2140/gt.2007.11.867},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/gt.2007.11.867/}
}