@article{MZ_1979__167_172850,
     author = {Christian U. Jensen and Peter Vamos},
     title = {On the {Axiomatizability} of {Certain} {Classes} of {Modules.}},
     journal = {Mathematische Zeitschrift},
     pages = {227--238},
     publisher = {mathdoc},
     volume = {167},
     year = {1979},
     zbl = {0387.03012},
     url = {http://geodesic.mathdoc.fr/item/MZ_1979__167_172850/}
}