@article{MOMA_1996__122_3_178746,
     author = {Luc Vrancken},
     title = {Thomsen {Surfaces} in {Affine} {4-Space.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {251--264},
     publisher = {mathdoc},
     volume = {122},
     number = {3},
     year = {1996},
     zbl = {0882.53012},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1996__122_3_178746/}
}