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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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