@TECHREPORT{11-2003,
    AUTHOR	= {Frédéric Gardi},
    TITLE	= {{A note on the Roberts characterization of proper and unit interval graphs}},
    INSTITUTION	= {{LIF}},
    ADDRESS	= {Marseille, France},
    TYPE	= {Research report},
    NUMBER	= {11-2003},
    MONTH	= {January},
    YEAR	= {2003},
    NOTE	= {http://pageperso.lif.univ-mrs.fr/~edouard.thiel/RESP/Rapports/11-2003.html},
}