BPS Saturated Amplitudes and Non-perturbative String Theory
arXiv:hep-th/9712079
Abstract
The study of the special F^4 and R^4 in the effective action for the Spin(32)/Z_2 and type II strings sheds some light on D-brane calculus and on instanton contribution counting. The D-instanton case is discussed separately.
latex 4 pages, crckapb style used. Cargese 1997 Gong show.v2 English corrected. v3 correction corrected