A TECHNIQUE TO ESTIMATE THE THREE DIMENSIONAL DIRECTIONALITY OF UNDERSEA AMBIENT NOISE R.A. WAGSTAFF, E.K. HOLMSTROM, B.A. BLUMENTHAL et R.W. TOWNSEN J. Phys. Colloques, 51 C2 (1990) C2-1017-C2-1020 DOI: 10.1051/jphyscol:19902238