1. http://www.geeksykings.eu/multigila/
2. http://ls11-www.cs.tu-dortmund.de/staff/klein/gdmult10
3. http://snap.stanford.edu/data/index.html
4. http://www.networkrepository.com/
5. Arleo, A., Didimo, W., Liotta, G., Montecchiani, F.: A distributed force-directed algorithm on Giraph: design and experiments. ArXiv e-prints (2016).
http://arxiv.org/abs/1606.02162