@article{GAMA_1974_1974_1_a10,
     author = {Ernesto, C. and  Lindgren, S.},
     title = {Homological transformations in four-dimensional space.},
     journal = {Gaceta matem\'atica},
     pages = {77-91},
     publisher = {mathdoc},
     volume = {26},
     number = {3-4},
     year = {1974},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/GAMA_1974_1974_1_a10/}
}