1. For a review and a list of references, see C. Dover: Quark dynamics ofN $$\bar N$$ annihilation, in: Lecture Notes in Physics, 243: Medium energy nucleon and antinucleon scattering. H.V. von Geramb, (ed.). Berlin, Heidelberg, New York: Springer 1985
2. A.M. Green:N $$\bar N$$ Annihilation into two mesons, Lectures at Les Houches, France (1987), HU-TFT-87-13
3. H.R. Rubinstein, H. Stern: Phys. Lett. 21 (1966) 447
4. An earlier calculation, hampered by the uncomplete knowledge of the meson spectrum, was made in H. Caprasse, J. Vandermeulen: Nuovo Cimento 6A (1971) 516
5. Particle Data Group: Review of particle properties, Phys. Lett. 170B (1986) 1