@article{MZ_1962__79_170080,
     author = {D.C.J. Burgess and R. McFadden},
     title = {Systems of ideals in partially ordered semigroups.},
     journal = {Mathematische Zeitschrift},
     pages = {439--450},
     publisher = {mathdoc},
     volume = {79},
     year = {1962},
     zbl = {0123.01804},
     url = {http://geodesic.mathdoc.fr/item/MZ_1962__79_170080/}
}