Write SQL query to solve given problem: List down the first name of patients who received "Influenza seasonal injectable preservative free" immunization.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT DISTINCT T1.first, T1.last FROM patients AS T1 INNER JOIN immunizations AS T2 ON T1.patient = T2.PATIENT WHERE T2.DESCRIPTION = 'Influenza  seasonal  injectable  preservative free'