[Reports] / Amer.inst.of aeronautics and astronautics. N 90-3990 : Application of beamform to sound propagation in the atmosphere / C.Gerhold,M.Wiese;Rep.presnted at AIAA 13th aeroacoustics conf.,Oct.22-24,1990,Tallahassee(Fl), 1990. - 11 c. - Текст : непосредственный.