@article{GT_2016_20_2_a5,
     author = {Burton, Benjamin and Colin de Verdi\`ere, \'Eric and de Mesmay, Arnaud},
     title = {On the complexity of immersed normal surfaces},
     journal = {Geometry & topology},
     pages = {1061--1083},
     publisher = {mathdoc},
     volume = {20},
     number = {2},
     year = {2016},
     doi = {10.2140/gt.2016.20.1061},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/gt.2016.20.1061/}
}