?url_ver=Z39.88-2004&rft_id=10.1108%2FWJE-03-2018-0086&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=A.A.&rft.aulast=Umar&rft.au=Umar%2C+A.A.&rft.issue=6&rft.volume=16&rft.issn=17085284&rft.atitle=Investigation+of+combined+effects+of+wax%2C+calcites+and+clay+on+emulsion+stability+using+response+surface+methodology&rft.pages=751-767&rft.title=World+Journal+of+Engineering&rft.date=2019&rft.genre=article