1. Completeness of Floyd logic;Andréka;Btdl. of the Section of Logic, Wrockzw (Lodz),1978
2. Completeness problems in verification of programs and program schemes;Andréka;MFCS '79, Sprhlger Lec. Notes Comp. Sci,1979
3. Henkin-type semantics for program schemes to turn negative results to positive;Andréka,1979
4. Program verification within and without logic;Andréka;Bull. of Section of Logic, Wroclaw (Lodz),1979
5. A characterization of Floyd provable program;Andréka;MFCS '81, Springer Lee. Notes Comp. Sei,1981