 In early 1979 Codd first presented some new ideas, called RM/T ('T' for Tasmania), at an invited talk for the "Australian Computer Science Conference" in Hobart, Tasmania.Later that year the ACM journal published a paper on RM/T, in which Codd acknowledges the influence of Schmid & Swensen (1975) and Wiederhold (1977).A later version of RM/T (we shall call it here "RM/D") was described by Chris Date in Date (1983) in which Date and Codd improved and refined RM/T, adding an entity type called "designative".