J. M. Tanner

James Mourilyan Tanner, DSc, MRCP, FRCPsych, FRCP (born 1 August 1920 – died 11 August 2010) was a British paediatric endocrinologist who was best known for his development of the Tanner scale, which measures the stages of sexual development during puberty. He was a professor emeritus of the Institute of Child Health at the University of London. https://en.wikipedia.org/wiki/James_Mourilyan_Tanner