Funding for this research was provided by:
National Science Foundation (CMMI-1452463, CMMI-1538746, CCF-1442635)
Text and Data Mining valid from 2018-06-05
Received: 11 October 2017
Accepted: 1 May 2018
First Online: 5 June 2018
: The author declares that he/she has no competing interests.
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