Data typeLog a deductive object oriented query language / René BalThe TM typing rules / René Bal, Herman Balsters, Rolf A. de ByDTL: a deductive and typed object-oriented language / C.M.R. Bal en H. BalstersTyping issues in a deductive object-oriented language / C.M.R. Bal, H. BalstersA deductive and typed object-oriented language / Martin Cornelis René BalNieuwe media : technologie beschikbaar; toepassing gezocht / tekst: C.M.R. Bal, M. Boreel ; red.: E.P. Reinders