?url_ver=Z39.88-2004&rft_id=10.1023%2FA%3A1009672832658&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.au=Higgins%2C+Andrew&rft.aulast=Higgins&rft.aufirst=Andrew&rft.issn=1572-9397&rft.title=Journal+of+Heuristics&rft.date=March+1997&rft.issue=1&rft.volume=3&rft.atitle=Heuristic+techniques+for+train+scheduling&rft.genre=article