
Journal for Geometry and Graphics 10 (2006), No. 1, 023036 Copyright Heldermann Verlag 2006 On a Special Pair of Parallel Congruences Despina Papadopoulou Dept. of Mathematics, Aristotle University, Thessaloniki, Greece papdes@math.auth.gr Pelagia Koltsaki Dept. of Mathematics, Aristotle University, Thessaloniki, Greece kopel@math.auth.gr The subject of this paper is the study of a special pair of parallel line congruences, i.e., line congruences with a common spherical image, in a threedimensional Euclidean space. Keywords: Ruled surfaces, line congruences. MSC: 53A25 [ Fulltextpdf (142 KB)] for subscribers only. 