|
Centre for Economic Policy Research (United Kingdom)
29
|
National Bureau of Economic Research (United States)
26
|
RAND Corporation (United States)
9
|
|
Urban Institute (United States)
8
|
Resources for the Future (United States)
3
|
Institute for European Environmental Policy (United Kingdom)
1
|
|
Mathematica Policy Research (United States)
1
|
Pembina Institute (Canada)
1
|
