Answer:
Avicenna > Greek philosophers & the Canon of Medicine
Averroes > ....?
Maimonides > study of the Jewish Torah
Explanation:
To start with Avicenna, he was a brilliant self-taught filosopher who admitted to have read <em>Metafysics </em>by Aristoteles a thousand times without understanding a single sentence, until he finally saw the (filosophical) light.
He also wrote the Canon of Medicine, a classic in Medicine, that was used in Europe (in Montpellier, France, to be precisely) as late as 1650. That is, some 600 years later.
Maimonides was a Jewish Philosopher who wrote in the Arabic language (!). Remember that in those long-gone days of religious harmony in Spain (that was ruled by the Arabs) Cristians, Arabs and Jews lived happily together.
One of his books was on the Jewish Torah.
Now, Averroes was a real genius (of the exact sciences), but also a bit too honest for this world. He right believed that only true filosophical logic could lead us to the real truth - finishing a thought that Socrates was developing and on which Immanuel Kant spend almost his entiry life.
Averroes got in trouble when he stated that the Koran and the Bible are alegoric stories for ignorant people...
Some people say he is the father of modern medicine; I would say he is the (ignored) father of wisdom.