Jaewoo Ahn Myung Ho Kim General-Purpose Text Entry Rules for Devices with 4x3 Configurations of Buttons. 223-231 2005 conf/iccsa/2005-1 ICCSA (1) http://dx.doi.org/10.1007/11424758_24 db/conf/iccsa/iccsa2005-1.html#AhnK05