00371pab a2200121 454500008004000000100001900040245009800059260000900157300001500166362000800181650002500189773003500214180718b2009   xxu||||| |||| 00| 0 eng d  aPerez, Carlota  aThe double bubble at the turn of the century: technological roots and structural implications  c2009  ap.779-805.  aJul  aTechnological change  aCambridge Journal of Economics