@article{MM2_1992__75_4_155723,
     author = {Ralph Berr},
     title = {The intersection theorem for orderings of higher level in rings.},
     journal = {Manuscripta mathematica},
     pages = {273--278},
     publisher = {mathdoc},
     volume = {75},
     number = {4},
     year = {1992},
     zbl = {0758.12003},
     url = {http://geodesic.mathdoc.fr/item/MM2_1992__75_4_155723/}
}