@article{MZ_1968__106_171013,
     author = {M. Friedberg and W.S. Mahavier},
     title = {Semigroups on {Chainable} and {Circle-like} {Continua.}},
     journal = {Mathematische Zeitschrift},
     pages = {159--161},
     publisher = {mathdoc},
     volume = {106},
     year = {1968},
     zbl = {0162.33001},
     url = {http://geodesic.mathdoc.fr/item/MZ_1968__106_171013/}
}