Xu Butian's appraisal is made by a professional department, which has nothing to do with the government and will not upload appraisal information, so it can't be found online.

Xu Butian, Han nationality, watch expert. Published a famous watch and a mirror, published by Tianjin Ancient Books Publishing House on 20 19. This book uses a large number of excellent reference books summarized from the actual research of famous watches.