MAP20100091586 Kleef, Richard C. van Risk-type concentration and efficiency incentives : a challenge for the risk adjustment formula / Richard C. van Kleef, Konstantin Beck and Florian Buchner En: Geneva papers on risk and insurance : issues and practice. - Geneva : The Geneva Association, 1976- = ISSN 1018-5895. - Tomo 35 Número 4 - 2010 I. Beck, Konstantin . II. Buchner, Florian .