Algorithms for effective transfer of ballast for an oil installation. - Kjetil Fagerholt; Sverre Inge Heimdal (J. Oper. Res. Soc., 1998)

Shortest path in the presence of obstacles: An application to ocean shipping. - Kjetil Fagerholt; Sverre Inge Heimdal; A. Loktu (J. Oper. Res. Soc., 2000)