"50.4" . . "''Heroj''-class submarine" . . "Heroj" . "Heroj (P-821)" . . . "7.05E8" . "Heroj-class submarine" . "37.04" . . "Heroj-class submarine" . . "6.14E8" . . . . . "Heroj (P-821) Junak (P-822) Uskok (P-823)" . . . . "''Heroj'' (P-821)" . "''Heroj'' class" .