@incollection{AST_2003__287__89_0,
     author = {Gutierrez, Carlos and Sarmiento, Alberto},
     title = {Injectivity of $C^1$ {Maps} $\mathbb{R}^2 \rightarrow \mathbb{R}^2$ at infinity and planar vector fields},
     booktitle = {Geometric methods in dynamics (II) : Volume in honor of Jacob Palis},
     editor = {de Melo, Wellington and Viana, Marcelo and Yoccoz, Jean-Christophe},
     series = {Ast\'erisque},
     pages = {89--102},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {287},
     year = {2003},
     mrnumber = {2040002},
     zbl = {1213.37028},
     language = {en},
     url = {http://www.numdam.org/item/AST_2003__287__89_0/}
}