@article{MAN_1966__167_161475,
     author = {E. ENGELER},
     title = {On {Structures} {Defined} by {Mapping} {Filters}},
     journal = {Mathematische Annalen},
     pages = {105--112},
     publisher = {mathdoc},
     volume = {167},
     year = {1966},
     zbl = {0149.24601},
     url = {http://geodesic.mathdoc.fr/item/MAN_1966__167_161475/}
}