[1] |
Bourbaki, N.: Elements of mathematics: general topology. (1989) · Zbl 0683.54003 |

[2] |
Dubois, D.; Prade, H.; Mo, X.: Semantic and algorithmic aspects of approximate reasoning in possibility theory. Rapport IRIT/90-53/R (1990) |

[3] |
Hellendoorn, H.: The generalized modus ponens considered as a fuzzy relation. Fuzzy sets and systems 46, 29-48 (1992) · Zbl 0773.03016 |

[4] |
James, I. M.: General topology and homotopy theory. (1984) · Zbl 0562.54001 |

[5] |
Kortelainen, J.: On modified set-operations. Åbo akademi reports on computer science and mathematics, 48-58 (1993) |

[6] |
Kripke, S. A.: Semantical considerations on modal logic. Acta philosophica fennica fasc. 16 (1963) · Zbl 0131.00602 |

[7] |
Lakoff, G.: Hedges: A study in meaning criteria and the logic of fuzzy concepts. The journal of philosophical logic 2, 458-508 (1973) · Zbl 0272.02047 |

[8] |
Mattila, J. K.: Calculus of modifier operators in fuzzy logic. Publications of the institute of applied mathematics no 14 (1989) |

[9] |
Mattila, J. K.: Modelling fuzziness by Kripke structures. Fuzzy engineering towards human friendly systems 2 (1991) |

[10] |
Patronis, T.; Stavrinos, P.: Fuzzy equivalence and resulting topology. Fuzzy sets and systems 46, 237-243 (1992) · Zbl 0776.04002 |

[11] |
Rasiowa, H.: An algebraic approach to non-classical logics. (1974) · Zbl 0299.02069 |

[12] |
Pawlak, Z.: Rough sets: A new approach to vagueness. Fuzzy logic for management of uncertainty (1992) |