/ശുദ്ധജല മത്സ്യക്കൃഷി Mathew, P M creator Mohan,M V text Vellanikkara Directorate of extension,Kerala Agricultural University 1989 5,rev monographic 108p. Sudhajala Malsyakrishi Shudhajala Malsyakrishi suthajala matsyakrushi matsyakrishi Malayalam Fresh water fish culture Aquaculture culture methods and processing Diseases and its treatments IR 639.31 MAT/SU