00363pab a2200133 454500008004000000100002200040245004600062260000900108300001700117362000800134650003800142650002000180773002900200180718b2010 xxu||||| |||| 00| 0 eng d aDafny, Leemore S. aAre health insurance markets competitive? c2010 ap.1399-1431. aSep aSocial security - Health services aSocial security aAmerican Economic Review