@article{AM2_1989__38_1_137331,
     author = {J. Vukman},
     title = {Symmetric bi-derivations on prime and semi-prime rings.},
     journal = {Aequationes mathematicae},
     pages = {245--254},
     publisher = {mathdoc},
     volume = {38},
     number = {1},
     year = {1989},
     zbl = {0687.16031},
     url = {http://geodesic.mathdoc.fr/item/AM2_1989__38_1_137331/}
}