@article{JRAM_1980__313_152196,
     author = {R. Mennicken and B. Sagraloff},
     title = {Characterizations of nearly-openness.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {105--115},
     publisher = {mathdoc},
     volume = {313},
     year = {1980},
     zbl = {0431.46001},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1980__313_152196/}
}