@article{CRMATH_2005__340_9_687_0,
     author = {Alfredo Berm\'udez and Pablo Gamallo and Mar{\'\i}a R. Nogueiras and Rodolfo Rodr{\'\i}guez},
     title = {Approximation properties of lowest-order hexahedral {Raviart{\textendash}Thomas} finite elements},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {687--692},
     publisher = {Elsevier},
     volume = {340},
     number = {9},
     year = {2005},
     doi = {10.1016/j.crma.2005.03.023},
     language = {en},
}