Funding for this research was provided by:
Belmont Forum DELTAS project (NE/L008726/1)
Article History
Received: 6 June 2017
Accepted: 3 April 2018
First Online: 27 April 2018
Ethics approval and consent to participate
: This article has been prepared using secondary data from General Statistical Office of Vietnam. Thus, no ethical approval was required for this study.
: The authors declare that they have no competing interests.
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