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  • Research Article
  • Open Access

Coincidence classes in nonorientable manifolds

Fixed Point Theory and Applications20062006:68513

  • Received: 15 September 2004
  • Accepted: 21 July 2005
  • Published:


We study Nielsen coincidence theory for maps between manifolds of same dimension regardless of orientation. We use the definition of semi-index of a class, review the definition of defective classes, and study the occurrence of defective root classes. We prove a semi-index product formula for lifting maps and give conditions for the defective coincidence classes to be the only essential classes.


  • Differential Geometry
  • Computational Biology
  • Product Formula
  • Root Classis
  • Coincidence Theory


Authors’ Affiliations

Departamento de Matemútica, Universidade Federal de Sáo Carlos, Rodovia Washington Luiz, Km 235, CP 676, Sáo Carlos, SP, 13565-905, Brazil


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© Daniel Vendrúscolo. 2006

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.