Albert... First, it would be better to write "I'm writing a review OF a poem BY Primo Levi. Second, because the author (the poet) is deceased (is dead) (deceased has a softer, more gentle term used to say someone has died), we would use the simple past tense. Therefore, "the author, (comma) AS I later found out (discovered = found out), (comma) was called Primo Levi.

Another soft way to say it is to refer to "the late Primo Levi." It is used for people who died within the fairly recent past, and would be appropriate for Primo Levi (1919-1987). In fact, on checking I find that a reviewer of a book "Primo Levi's Universe: A Writer's Journey," said, "Commemorating the late Primo Levi's 90th birthday, this extended essay interweaves the writer's tragic life with his work."