In situ target strength measurement of selar boops (Oxeye sead) and megalaspis cordyla (Torpedo sead) in South China Sea / by Jafri Din, author, Adil Mohd., 1979-, author, Sunardi, author, Raja Bidin Raja Hassan, author, Nadzri Seman, author, Symposium on the Approach with Fisheries Acoustics and Complementary Technologies (2008: Norway)