Ordinal Excitation of Three-Magnon and Four-Magnon Processes of Magnetostatic Surface Waves in YIG Films S. Jun, S.A. Nikitov, R. Marcelli, P. De Gasperis et J. Pelzl J. Phys. IV France, 07 C1 (1997) C1-457-C1-458 DOI: 10.1051/jp4:19971186