1. S. Godfrey, M. Pennington, E. v Beveren, N. Torqvist, J. Weinstein, N. Achasov; talks at this conference.
2. RAL-90-030 “Amplitude analysis of γγ → ππ from threshold to 1.4 GeV”;Morgan,1990
3. K. Seth, private communication, M. Macri, this conference.
4. W. Lockmann, L. Chen, M. Burchell, L. Stanco, talks at this conference.
5. A polarization prediction from two-gluon exchange for