1. Shankar, R.: Rev. Mod. Phys. 66, 129 (1994)
2. Harvey, J., Polchinski, J. (eds.): Proceedings of the 1992 Theoretical Advanced Studies Institute in Elementary Particle Physics. World Scientific, Singapore (1993). hep-th/9210046
3. Gies, H.: Lectures in this Volume. hep-ph/0611146
4. Metzner, W., Salmhofer, M., Honerkamp, C., Meden, V., Schönhammer, K.: arXiv:1105.5289
5. Landau, L.D.: Sov. Phys. JETP 3, 920 (1957)