Please list the top three patients' birthdays with the highest glutamic pylvic transaminase in the normal range.
highest glutamic pylvic transaminase in the normal range refers to MAX(GPT < 60);
SELECT T1.Birthday FROM Patient AS T1 INNER JOIN Laboratory AS T2 ON T1.ID = T2.ID WHERE T2.GPT < 60 ORDER BY T2.GPT DESC LIMIT 3