Improved Algorithms for Routing on Two-Dimensional Grids. - Dinesh Bhatia; Frank Thomson Leighton; Fillia Makedon; Carolyn Haibt Norton (WG, 1992)

Using Separation Algorithms in Fixed Dimension. - Carolyn Haibt Norton; Serge A. Plotkin; Éva Tardos (J. Algorithms, 1992)