Funding for this research was provided by:
The Mäxi Foundation, Zurich, Switzerland
Received: 10 April 2018
Accepted: 19 September 2018
First Online: 26 September 2018
Ethics approval and consent to participate
: All the data supporting our findings in this paper were freely downloaded from the UN agencies’ websites. No ethical approval or written informed consent for participation was required.
: Not applicable.
: The authors declare that they have no competing interests.
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