Tezer, Cem
This paper is concerned with an elementary problem of V. Thebault which has remained unsolved until recently. We offer a natural solution of the problem and relate it to the classical notable configurations of the triangle.


On endomorphisms of surface mapping class groups
Korkmaz, Mustafa (Elsevier BV, 2001-05-01)
In this paper, we prove that every endomorphism of the mapping class group of an orientable surface onto a subgroup of finite index is in fact an automorphism.
On homotopy groups of real algebraic varieties and their complexifications
Ozan, Yıldıray (Springer Science and Business Media LLC, 2004-10-01)
Let X-0 be a topological component of a nonsingular real algebraic variety and i : X --> X-C is a nonsingular projective complexification of X. In this paper, we will study the homomorphism on homotopy groups induced by the inclusion map i: X-0 --> X-C and obtain several results using rational homotopy theory and other standard tools of homotopy theory.
Finite rigid sets in curve complexes of nonorientable surfaces
Ilbira, Sabahattin; Korkmaz, Mustafa (Springer Science and Business Media LLC, 2020-06-01)
A rigid set in a curve complex of a surface is a subcomplex such that every locally injective simplicial map from the set into the curve complex is induced by a homeomorphism of the surface. In this paper, we find finite rigid sets in the curve complexes of connected nonorientable surfaces of genus g with n holes for g + n not equal 4.
Some cardinal invariants on the space C-alpha (X, Y)
Onal, S; Vural, C (Elsevier BV, 2005-05-14)
Let C-alpha (X, Y) be the set of all continuous functions from X to Y endowed with the set-open topology where a is a hereditarily closed, compact network on X such that closed under finite unions. We define two properties (E1) and (E2) on the triple (alpha, X, Y) which yield new equalities and inequalities between some cardinal invariants on C-alpha (X, Y) and some cardinal invariants on the spaces X, Y such as:
Liftable homeomorphisms of cyclic and rank two finite abelian branched covers over the real projective plane
Atalan, Ferihe; Medetogullari, Elif; Ozan, Yıldıray (Elsevier BV, 2021-02-01)
© 2020 Elsevier B.V.In this note, we investigate the property for regular branched finite abelian covers of the real projective plane, where each homeomorphism of the base (preserving the branch locus) lifts to a homeomorphism of the covering surface.
Citation Formats
H. DEMIR and C. Tezer, “REFLECTIONS ON A PROBLEM OF THEBAULT,V.,” GEOMETRIAE DEDICATA, pp. 79–92, 1991, Accessed: 00, 2020. [Online]. Available: