1. Understanding fine structure constants and three generations
2. Origin of symmetries;Froggatt,1991
3. Fitting the fine structure constants by critical couplings and integers;Bennett,1992
4. D.L. Bennett and H.B. Nielsen, Predictions for nonabelian fine structure constants from multicriticality, NBI preprint NBI-HE-93-22
5. Lecture given by HBN at the XVIII Symposium on High Energy Physics;Brene,1984-1985