This is a copy of the GTL (Graph Template Library) from http://www.fim.uni-passau.de/en/fim/faculty/chairs/theoretische-informatik/projects.html. The original authors are Michael Forster, Andreas Pick, and Marcus Raitner. Their code is licensed under both the GPL and LGPL.
rdmpage/graph-template-library
GTL (Graph Template Library) is a STL based library, which provides necessary classes and algorithms for the work with graphs.
C++LGPL-3.0