A uniform framework for orientation relations based on distance comparison.

Tiansi Dong Hans W. Guesgen A uniform framework for orientation relations based on distance comparison. 75-82 2008 IEEE ICCI http://dx.doi.org/10.1109/COGINF.2008.4639153 conf/IEEEicci/2008 db/conf/IEEEicci/IEEEicci2008.html#DongG08