@article{MM2_1989__63_3_155367,
     author = {Erik Valtonen},
     title = {Some {Homological} properties of commutative semitrivial ring extensions.},
     journal = {Manuscripta mathematica},
     pages = {45--68},
     publisher = {mathdoc},
     volume = {63},
     number = {3},
     year = {1989},
     zbl = {0669.13003},
     url = {http://geodesic.mathdoc.fr/item/MM2_1989__63_3_155367/}
}