Funding for this research was provided by:
Higher Education Commission, Pakistan (5192/KPK/NRPU/R&D/HEC/2016)
Text and Data Mining valid from 2019-07-23
Received: 12 April 2019
Accepted: 7 July 2019
First Online: 23 July 2019
Compliance with ethical standards
: On behalf of all authors, the corresponding author declares that there is no conflict of interest.