1. Dept. of Transportation, Logistics, and Finance, Upper Great Plains Transportation Institute, North Dakota State Univ., Fargo, ND.
2. Dept. of Civil and Environmental Engineering, Univ. of Massachusetts Amherst, Amherst, MA.
3. Dept. of Civil and Environmental Engineering, Univ. of Maryland, College Park, MD.
4. Upper Great Plains Transportation Institute, North Dakota State Univ., Fargo, ND.