CREATE TABLE ABC (A  NUMBER);
insert into abc values(1);
insert into abc values(9);
insert into abc values(13);
insert into abc values(999);

CREATE OR REPLACE PACKAGE ref_cur_tst
IS
   CURSOR c1 IS SELECT a FROM abc;
   TYPE t_cur IS REF CURSOR RETURN c1%ROWTYPE;

   PROCEDURE get_abc (cv_cur IN OUT t_cur);
END ref_cur_tst;
/

CREATE OR REPLACE PACKAGE BODY ref_cur_tst
AS
   PROCEDURE get_abc (cv_cur IN OUT t_cur)
   IS
   BEGIN
      OPEN cv_cur FOR SELECT a FROM abc;
   END get_abc;
END ref_cur_tst;
/

-- (sqlplus) set serveroutput on;

DECLARE
   a       abc.a%TYPE;
   cv_c1   ref_cur_tst.t_cur;
BEGIN
   ref_cur_tst.get_abc (cv_c1);

   LOOP
      FETCH cv_c1 INTO a;
      EXIT WHEN cv_c1%NOTFOUND;
      DBMS_OUTPUT.put_line (a);
   END LOOP;
   CLOSE cv_c1;
END;
/

-- dummy cursor to get %rowtype below
-- no joins even required - it's just to get the structure
   CURSOR c1 IS SELECT a.ename, b.deptname FROM emp a, dept b;
   TYPE t_cur IS REF CURSOR RETURN c1%ROWTYPE;


-- or just use emp%rowtype to match whole table structure (strong ref cursor).
TYPE t_cur IS REF CURSOR RETURN emp%ROWTYPE;


-- or just define a weak ref cursor.
TYPE t_cur IS REF CURSOR;