Some Recent Results on Signed Graphs with Least Eigenvalues ≥ -2

  • G. R. Vijayakumar
  • N. M. Singhi
Part of the The IMA Volumes in Mathematics and Its Applications book series (IMA, volume 20)


A survey of some results concerning the class of sigraphs represented by root-systems D n, n ∈ N and E 8 is given and some unsolved problems are described.


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Copyright information

© Springer-Verlag New York, Inc. 1990

Authors and Affiliations

  • G. R. Vijayakumar
    • 1
  • N. M. Singhi
    • 1
  1. 1.School of MathematicsTata Institute of Fundamental ResearchColaba, BombayIndia

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