?url_ver=Z39.88-2004&rft_id=10.3390%2Fma12142291&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=N.&rft.au=Shafiq%2C+N.&rft.aulast=Shafiq&rft.issue=14&rft.volume=12&rft.issn=19961944&rft.atitle=Effects+of+modified+metakaolin+using+nano-silica+on+the+mechanical+properties+and+durability+of+concrete&rft.title=Materials&rft.date=2019&rft.genre=article