I was looking for the same claim about another mathematician (namely Vazgain Avanissian) that I came to this question. Following the clues left by the previous answer and the comments, I found a mention of Pierre Fatou in [Project Euclid][1]. Fatou has been mentioned in the OP's comment. However, the piece below includes added information. It neither answer OP's questions asked in the body of the question, nor any information about the mathematician whom I am looking for. But it gives an answer to the "any" part of the title: "any other mathematician ...". I hope, this in turns leads someone else to a better picture of the situation.    
[![enter image description here][2]][2]


  [1]: https://www.projecteuclid.org/download/pdf_1/euclid.bams/1183424800
  [2]: https://i.sstatic.net/1WehO.png