Creating Tables
Person(ssn NUMERIC(9), name VARCHAR(40), gender CHAR(1)), ssn is primary key

Organization(org_code CHAR(4), budget INTEGER, org_name VARCHAR(60)), org_code is primary key

Person_Organization(ssn, org_code), both columns are the primary key.

CREATE TABLE person_organization(ssn NUMERIC(9), org_code VARCHAR(60));

create table person_organization
( ssn number(9)
, org_code varchar2(60)
, constraint person_organization_pk primary key (ssn, org_code)
, constraint person_organization_ssn_fk foreign key ( ssn )
    references person ( ssn )
, constraint person_organization_oc_fk foreign key ( org_code )
    references organization ( org_code )
 );

CREATE TABLE Persons (
  ssn int(9) NOT NULL PRIMARY KEY,
  name varchar(40),
  gender CHAR(1)
)

CREATE TABLE Organization (
  org_code CHAR(4)NOT NULL PRIMARY KEY,
  budget INTEGER,
  org_name VARCHAR(60)
)

CREATE TABLE Person_Organization (
  ssn int FOREIGN KEY REFERENCES Persons(ssn),
  org_code CHAR FOREIGN KEY REFERENCES Organization(org_code)