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               <dc:title>Horospheres in hyperbolic geometry</dc:title>
               <dc:creator>Gallego Gómez, Eduardo</dc:creator>
               <dc:creator>Reventós, Agustí</dc:creator>
               <dc:creator>Centre de Recerca Matemàtica</dc:creator>
               <dc:subject>Geometria hiperbòlica</dc:subject>
               <dc:subject>Espais de curvatura constant</dc:subject>
               <dc:description>In this paper we investigate the role of horospheres in Integral Geometry and Differential Geometry. In particular we study envelopes of families of horocycles by means of "support maps". We define invariant "linear combinations" of support maps or curves. Finally we obtain Gauss-Bonnet type formulas and Chern-Lashof type inequalities.</dc:description>
               <dc:date>2008</dc:date>
               <dc:type>Article</dc:type>
               <dc:type>Prepublicació</dc:type>
               <dc:relation>Centre de Recerca Matemàtica. Prepublicacions ;</dc:relation>
               <dc:rights>open access</dc:rights>
               <dc:rights>Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades.</dc:rights>
               <dc:rights>https://creativecommons.org/licenses/by-nc-nd/2.5/</dc:rights>
               <dc:publisher>Centre de Recerca Matemàtica</dc:publisher>
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