Despite his profound effect on Persian life and culture and his enduring popularity and influence, few details of his life are known, and particularly about his early life there is a great deal of more or less mythical anecdote. Some of the early tazkeras (biographical sketches) mentioning Hafez are generally considered unreliable. One early document discussing Hafez' life is the preface of his Divān, which was written by an unknown contemporary of Hafez whose name may have been Moḥammad Golandām. The generally accepted modern edition of Hafez's Divān is known as "Qazvini-Ḡani", edited by Moḥammad Qazvini and Qāsem Ḡani.