The excess incidence of squamous cell esophageal cancer among us black men. Role of social class and other risk factors. - Brown L; Hoover R; Silverman D; Baris D; Hayes R; Swanson G; Schoenberg J; Greenberg R; Liff J; Schwartz A; Dosemeci M; Pottern L; et al. (Annals of epidemiology, 2000)