@article{JRAM_1975__272_151523,
     author = {Claus Michael Ringel and H. Tachikawa},
     title = {QF-3 rings.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {49--72},
     publisher = {mathdoc},
     volume = {272},
     year = {1975},
     zbl = {0318.16006},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1975__272_151523/}
}