- Received September 16, 2014
- Accepted September 22, 2014
- First published November 4, 2014.
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Files in this Data Supplement:
- Data supplement 1 - Online appendix 1
- Data supplement 2 - Online appendix 2
- Data supplement 3 - Online appendix 3
- Data supplement 4 - Online appendix 4
- Data supplement 5 - Online appendix 5
- Data supplement 6 - Online appendix 6
- Data supplement 7 - Online appendix 7
- Data supplement 8 - Online appendix 8
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