?url_ver=Z39.88-2004&rft_id=https%3A%2F%2Fdx.doi.org%2F10.54203%2Fscil.2020.wvj70&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=H.+M.+S.&rft.au=Hassan%2C+H.+M.+S.&rft.aulast=Hassan&rft.atitle=Effect+of+L-Carnitine+and+Yeast+Chromium+Supplementation+on+Productive+Performance+in+Pekin+and+Sudani+Duckling+during+Growth+Period&rft.volume=10&rft.title=World's+Veterinary+Journal&rft.issue=4&rft.pages=587-596&rft.issn=23224568+(ISSN)&rft.date=25+December+2020&rft.genre=article