1. A commercial bibliographic dATabase and retrieval service from DIALOG InformATion Services. 2. Interactive mAThemATics using a graphics tablet by Illinois Inst Tech, 1966. ["DIALOG: A ConversATional Programming System with a Graphical OrientATion", S.H. Cameron et al, CACM 10:349-357 (1967). Sammet 1969, p.255-258].