Euler's Theorem
    Discussion and application of Euler's formula,
    by Ludmil Katzarkov, U.C.I .
Four Color Theorem  
    A discussion of  Appel and Haken's proof and a proposed
    new proof by Neil Robertson, Daniel P. Sanders, Paul Seymour
    and Robin Thomas, Georgia Tech
The Four Color Theorem    
    A nice historical survey of the Theorem.
    J J O'Connor and E F Robertson
The Four Color Theorem - An excellent discussion of the history
    and variety of approaches to this problem.  Part of  MathPages.
Graph Theory
    A brief history of graph theory, along with an impressive array of
    basic and advanced definitions, by Stephen C. Locke,
    Florida Atlantic University.
Graph Theory
    Discussion of  topics of graph theory, ranging from circuits
    to trees.  Eric Weisstein's World of Mathematics (MathWorldTM) 
Graph Theory and Enumeration
    An on-line course in the basics of graph theory,
    by Dale Winter, at Michigan Math Scholars  
Graph Theory Lessons
    A set of lessons on various topics in graph theory,
    by Christopher P. Mawata
    University of Tennessee at Chattanooga
Graph Theory Open Problems
    A list of problems not yet solved in graph theory,
    from Rutgers University.
Graph Theory on the Web
    Links to relevant sites on the Internet
Graph Theory Tutorials  
    a series of short interactive tutorials introducing the basic
    concepts of graph theory, by Chris K. Caldwell, The University
    of Tennessee at Martin
Graphs and Graph Theory
    Links to definitions of words used in graph theory,
    by MegaMathematics , Los Alamos National Lab .
Graphs: Euler and Hamiltonian Circuits
    Some definitions and discussions by Evan Fletcher, U. C. Davis.
Overview on Graph Theory
    A survey of basic ideas and terms of the subject,
    from Leibniz Laboratory, The Graph Theory Team
    (part of the IMAG Institute, Grenoble, France).
Nineteen Proofs of Euler's Formula
    Surprisingly many different ways of doing this proof.  
    From the Geometry Junkyard, David Eppstein, UC Irvine.
Revised 6-23-09