1. M. Cvetič and S. Godfrey, hep-ph/9504216; J. L. Hewett and T. G. Rizzo, Phys. Rep. 183, 193 (1989).
2. N. Arkani-Hamed et al., Phys. Lett. B 429, 263 (1998), hep-ph/9803315; I. Antoniadis et al., Phys. Lett. B 436, 257 (1998), hep-ph/9804398; L. Randall and R. Sundrum, Phys. Rev. Lett. 83, 3370, 4690 (1999), hep-ph/9905221, hep-th/9906064; C. Kokorelis, Nucl. Phys. B 677, 115 (2004), hepth/0207234.
3. A. Leike, Phys. Rept. 317, 143 (1999), hepph/9805494.
4. D. Bourilkov, hep-ph/0305125; CERN-CMSNOTE-2006-085.
5. V. A. Matveev, R. M. Muradyan, and A. N. Tavkhelidze, Preprint No. R2-4543, OIYaI (Joint Inst. Nucl. Res., Dubna, 1969); S. D. Drell and T. M. Yan, SLAC-PUB-0755 (June 1970);