Prevalence of monoclonal gammopathy of undetermined significance (MGUS) among farmers involved in open field farming and/or cattle breading in France. Issue 7 (2nd July 2016) - Lecluse, Yannick; Comby, Elisabeth; Mariotte, Delphine; Tual, Séverine; Le Mauff, Brigitte; Lebailly, Pierre; Gauduchon, Pascal