?url_ver=Z39.88-2004&rft_id=10.21833%2Fijaas.2020.03.001&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=I.&rft.au=Hassan%2C+I.&rft.aulast=Hassan&rft.atitle=Accurate+cost+estimation+for+software+with+volatile+requirements&rft.pages=1-8&rft.volume=7&rft.issn=2313626X&rft.issue=3&rft.date=2020&rft.title=International+Journal+of+Advanced+and+Applied+Sciences&rft.genre=article