SQL Create table with foreign key

On 07.07.12, In 116, php, by sc_7cabc029490e9fcb99b8d58793c625bd
needed to figure out how to create a table that references a foreign key
CREATE TABLE askeys (  
    id INT AUTO_INCREMENT PRIMARY KEY,  
    user_id INT,  
    askey VARCHAR(250),
    assecretkey VARCHAR(250),
    FOREIGN KEY (user_id) REFERENCES users(user_id)  
);