1. For a recent review, see K. Lingel, T. Skwarnicki, J.G. Smith, hep-ex/9804015.
2. For earlier studies, L.L. Chau, H.Y. Cheng, W.K. Sze, H. Yao, B. Tseng, Phys. Rev. D 43 (1991) 2176; D 45 (1992) 3143, G. Kramer, W.F. Palmer, H. Simma, Z. Phys. C 66 (1995) 429; Nucl. Phys. B 428 (1994) 77. J.-M. Gérard, W.S. Hou, Phys. Rev. Lett. 62 (1989) 855; Phys. Rev. D 43 (1991) 2909.
3. D. Atwood, A. Soni, Phys. Lett. B 405 (1997) 150; Phys. Rev. Lett. 79 (1997) 5206.
4. Enhancedb→sgDecay, Inclusiveη′Production, and the Gluon Anomaly
5. The gluonic decay of the b-quark and the η′-meson