?url_ver=Z39.88-2004&rft_id=10.1088%2F1757-899X%2F226%2F1%2F012073&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.aufirst=M.&rft.au=Ayoub%2C+M.&rft.aulast=Ayoub&rft.date=2017&rft.issn=17578981&rft.title=Conversion+of+glycerol+to+polyglycerol+over+waste+duck-bones+as+a+catalyst+in+solvent+free+etherification+process&rft.genre=proceeding