@article{SIGMA_2018_14_a95,
     author = {Sara Froehlich},
     title = {The {Variational} {Bi-Complex} for {Systems} of {Semi-Linear} {Hyperbolic} {PDEs} in {Three} {Variables}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2018},
     volume = {14},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2018_14_a95/}
}