Funding for this research was provided by:
China Scholarship Council (201506560001)
Article History
Received: 23 January 2018
Accepted: 17 August 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: The travel survey data are freely available from “DANS” website (the Netherlands institute for permanent access to digital research resources). The data were approved by the Statistics Netherlands Protection Authority.
: Not applicable.
: The authors declare that they have no competing interests.
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