@TechReport{Blackburn_Tzakova:1998_1,
      AUTHOR = {Blackburn, Patrick and Tzakova, Miroslava},
      TITLE = {Hybrid Languages and Temporal Logic (Full Version)},
      YEAR = {1998},
      MONTH = {July},
      NUMBER = {96},
      PAGES = {50},
      ADDRESS = {Saarbrücken},
      TYPE = {CLAUS Report},
      INSTITUTION = {Universität des Saarlandes},
      URL = {ftp://ftp.coli.uni-sb.de/pub/coli/claus/claus96.ps ftp://ftp.coli.uni-sb.de/pub/coli/claus/claus96.dvi},
      ABSTRACT = {Hybridization is a method invented by Arthur Prior for extending the expressive power of modal languages. Although developed in interesting ways by Robert Bull, and the Sofia school (notably, George Gargov, Valentin Goranko, Solomon Passy and Tinko Tinchev), the method remains little known. In our view this has deprived temporal logic of a valuable tool. The aim of the paper is to explain why hybridization is useful in temporal logic. We make two major points, the first technical, the second conceptual. Technically, we show that hybridization gives rise to well-behaved logics that exhibit an interesting synergy between modal and classical ideas. This synergy, obvious for hybrid languages with full first-order expressive strength, is demonstrated for three weaker local languages, all of which are capable of defining the Until operator; we provide simple minimal axiomatizations for all three systems, and show that in a wide range of temporally interesting cases, extended completeness results can be obtained automatically. Conceptually, we argue that the idea of sorted atomic symbols which underpins the hybrid enterprise can be developed much further. To illustrate this, we discuss the advantages and disadvantages of a simple hybrid language which can quantify over paths. This is the original version of a paper which was accepted for publication in a special issue of the Journal of the IGPL on temporal logic. Unfortunately, the length of the article meant that it had to be drastically cut, and only a shorter version will appear. While the short version covers one of the most elegant results (@-driven completeness results) and is slightly more up to date in certain respects, the long version is probably the most detailed discussion of the completeness theory of local hybrid languages around. The long version also contains many lengthy footnotes. These outline the history of hybrid languages in considerable detail, and contain many remarks on philosophical, methodological, and technical issues.},
      ANNOTE = {COLIURL : Blackburn:1998:HLTa.pdf Blackburn:1998:HLTa.ps Blackburn:1998:HLTa.dvi}
}