In MySQL how do I create a stored procedure that takes multiple parameters?

Example of function: call getThings(amount, place, limit, marginError)

SYNOPSIS: CALL getThings(4, PA, 3, 1.2);

example of goal:

CREATE PROCEDURE getThings(IN amount X, place VARCHAR(30), lim INT, marginError double)
SELECT place, limit, amount
FROM AREA, PRODUCT
WHERE AREA.place=PRODUCT.place
AND PRODUCT.AREA=place
ORDER BY ABS(AMOUNT-marginError)
LIMIT lim;
END

Desired goal is to retrieve the closest 3 products from a stored procedure (using MySQL) but I keep getting sytax errors in trying to create the procedure.