@article{JEMS_2016_18_4_a0,
     author = {Alex Fink and Luca Moci},
     title = {Matroids over a ring},
     journal = {Journal of the European Mathematical Society},
     pages = {681--731},
     publisher = {mathdoc},
     volume = {18},
     number = {4},
     year = {2016},
     doi = {10.4171/jems/600},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/600/}
}