Geometriae Dedicata

, Volume 29, Issue 3, pp 311–315 | Cite as

Matroids without adjoint

  • Achim Bachem
  • Alfred Wanka


The purpose of this note is to give an example of a rank-4 matroid which not only shows that Levi's intersection property is not a sufficient condition for the existence of an adjoint but also seems to have an interesting structure of the lattice of flats.


Extension Lattice Separation Theorem Oriented Matroids Geometric Lattice Extension Equivalence 
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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Achim Bachem
    • 1
  • Alfred Wanka
    • 1
  1. 1.Mathematisches InstitutUniversität KölnKöln 41Germany

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