The doctrine of Wahdatul-Wajood presented by?

The doctrine of Wahdatul-Wajood presented by?

وحدت الوجود کا نظریہ کس نے پیش کیا؟
Explanation

Ibn-al-Arabi propounded the Sufi philosophy of wahdat-ul-wujud 

Wahdat-ul-Wujud means onceness of being.

He was one of the greatest Muslim philosophers.