@article{SMJ2_2020_46_2_a4,
     author = {Milousheva, Velichka and Aleksieva, Yana},
     title = {Quasi-minimal {Lorentz} surfaces in pseudo-euclidean 4-space with neutral metric},
     journal = {Serdica Mathematical Journal},
     pages = {151--164},
     publisher = {mathdoc},
     volume = {46},
     number = {2},
     year = {2020},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_2020_46_2_a4/}
}