1[1]S. C. Nardone, V. J. Aidala. Observability0 Criteria for Bearing - Only Target Motion Analysis. IEEE Transactions on aerospace and Electronic systems ,Mar. 1981 ;Vol. AES- 17:161-166
2[2]Peggy J. Galkowski, Mohammed A. Islam.an Alternative Derivation of the Modified Gain Function of Song and Speyer. IEEE Transactions on Automatic Control, September 1991; vol. AC - 36,No. 11:1323-1326
3[3]Hammel. S. E. , V. J. Aidala. Observability Requirements for Three-Dimensional Tracking via Angle Measurements. IEEE Trans. , March 1985;Vol. AES 21, No. 2: 200- 207
4[4]Guelle I, Durif J. Inter- array data association and target motion analysis. Underwater Acoustic Data Processing, 1989: 525- 529
5[5]S. Koteswara Rao. Modified Gain Extended Kalman Fillter with Application to Angles only Underwater passive Target Tracking. Proceedingsof ICSP'98:1439 - 1442