?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Nguyen%2C+Duc+Manh&rft.aulast=Nguyen&rft.aufirst=Duc+Manh&rft.date=2019&rft.title=An+Efficient+Column+Generation+Approach+for+Solving+the+Routing+and+Spectrum+Assignment+Problem+in+Elastic+Optical+Networks&rft.genre=proceeding