Publications

E. Herrmann: About Lindenbaum functions of ℵ₀-categorical theories in: Bull. Acad. Polon. des Sciences, Ser. Math. Astr. Vol. XXIV (1976)

E. Herrmann: A note on no-hh-simple recursively enumerable sets in: Bull. Acad. Polon. des Sciences, Ser. Math. Astr. Vol. XXV (1977), 333 - 336

E. Herrmann: Der Verband der rekursiv aufzählbaren Mengen in: Seminarbericht Nr. 10 der Sektion Mathematik der Humboldt - Universit¨at, Berlin (1978)

E. Herrmann: The lattice structure of the recursively enumerable sets in: Fundamentals of Computation Theory , FCT’79 DDR, Akademie Verlag, Berlin (1979), 175 - 181

E. Herrmann, H. Wolter: Untersuchungen zu schwachen Logiken der zweiten Stufe in: Zeitschrift für mathematische Logik und Grundlagen der Mathematik (1980)

E. Herrmann: Verbandseigenschaften der rekursiv aufzählbaren Mengen in: Seminarbericht Nr. 36 der Sektion Mathematik der Humboldt-Universität, Berlin (1981)

E. Herrmann: Orbits of hyperhypersimple sets an the lattice of Σ⁰₃-sets in: The Journal of Symbolic Logic Vol. 48 No. 3 (1983), 693 - 699

E. Herrmann: Major Untermengen von hyperhypersimplen Mengen und Idealfamilien. Dissertation B. Sektion Mathematik der Humboldt-Universität, Berlin (1983)

E. Herrmann: Definable Boolean pairs in the lattice of recursively enumerable sets in: Proceedings of the First Easter Conference on Model Theory. Seminarbericht Nr. 49 der Sektion Mathematik der Humboldt-Universität, Berlin (1983), 42 - 67

E. Herrmann: Definable structures in the lattice of recursively enumerable sets in: The Journal of Symbolic Logic Vol. 49 No. 4 (1984), 1190 - 1197

E. Herrmann: The Undecidability of the elementary theory of the lattice of recursively enumerable sets in: Frege Conference 1984. Proceedings of the International Conference held at Schwerin (GDR) (1984), 66 - 72

E. Herrmann: Classes of simple sets, filter properties and their mutual position in: Proc. of the 2. Conf. on Model theory, Wittenberg, 1984. Seminarbericht Nr. 60 der Sektion Mathematik der Humboldt-Universität , Berlin (1984), 60 - 72

E. Herrmann: Maximal Sets. A survey on the maximal sets inside the theory of the r.e. sets and their degrees. typewritten manuscript (1985)

E. Herrmann: Extended lattices and Boolean pairs in: Proc.of the 3rd Conf. on Model theory, Groß Köris, 1985. Seminarbericht Nr. 70 der Sektion Mathematik der Humboldt-Universität, Berlin (1985), 115 - 133

E. Herrmann: The Index set {e : W_e ≡₁ X } in: The Journal of Symbolic Logic Vol. 51 No. 3 (1986), 110 - 116

E. Herrmann: Automorphisms of the lattice of recursively enumerable sets and hyperhypersimple sets in: Proc. of the 4th Conf. on Model theory Groß Köris, 1986. Seminarbericht Nr. 86 der Sektion Mathematik der Humboldt-Universität, Berlin (1986), 69 - 109

E. Herrmann: Automorphisms of the lattice of recursively enumerable sets and hyperhypersimple sets in: Proc. of the 8.th Int. Conf. of Logic, Math., Phil., Science, Moscow, 1987. Studies in logic Vol.126 North Holland (1989), 179 - 190 (revised and shortened version)

E. Herrmann, R. Downey: Review of Robert I. Soare: Recursively enumerable sets and degrees. A study of computable functions and computable sets in: The Journal of Symbolic Logic Vol. 55 No. 1 (1990), 356 - 357

E. Herrmann: 1-reducibility inside an m-dedree with a maximal set in: The Journal of Symbolic Logic Vol. 57 No. 3 (1992), 1046 - 1056

E. Herrmann, M. Kummer: Diagonals and D-maximal sets in: The Journal of Symbolic Logic Vol. 59 No. 1 (1994), 60 - 72

E. Herrmann: On the ∀∃- theory of the factor lattice by the major subset relation in: S.B. Cooper, T.A. Slaman, S.S. Wainer: Computability, Enumerability, Unsolvability, Direction in Recursion theory. London Math. Soc., Lecture Note Series No. 224, Cambridge Press (1996), 139 - 166

E. Herrmann: Finite End Intervals in Factor Lattices of the Lattice of r.e. sets respectively to Congruence relations of this lattice in: Proceedings of the Conference in Oberwolfach, January 1996 (1996)

E. Herrmann: Boolean Pairs Formed by the Delta⁰_n-Sets in: Annals of Pure and Applied Logics Vol. 87 No. 2 (1997), 145 - 149

E. Herrmann: Recursively enumerable sets. The lattice structure under inclusion and general properties of the recursively enumerable sets. typewritten manuscript (1998)

E. Herrmann: Definability of the Σ⁰₄-acceptable ideals. Talk in the AMS-Meeting in Boulder, Colorado (June 1999)

E. Herrmann: Infinite chains and antichains in recursive partial orderings in: Journal of Symbolic Logic (2001)

P. Cholak, R. Coles, R. Downey, E. Herrmann: Automorphisms of the lattice of π₁⁰-classes, perfect thin classes and anc degrees in: Transactions Amer. Math. Soc. Vol. 353 No. 12 (2001), 4899 - 4924

P. Cholak, R. Downey, E. Herrmann: Some Orbits for 𝓔* in: Annals Pure and Appl. Logic (2001)

E. Herrmann: 𝒓-Maximal Sets. Humboldt-Universität Berlin, 2005