@article {IOPORT.03700893,
    author       = {Rival, Ivan},
    title        = {The problem of fixed points in ordered sets.},
    year         = {1980},
    journal      = {Annals of Discrete Mathematics. North-Holland Publishing Company, Amsterdam etc. North-Holland Mathematics Studies.},
    volume       = {8},
    pages        = {283-292},
    identifier   = {03700893},
}