The 2nd. most productive stage of the human being is from 70 to 80 years of age.
The 3rd. most productive stage is from 50 to 60 years of age.
in NEW ENGLAND JOURNAL OF MEDICINE
The 2nd. most productive stage of the human being is from 70 to 80 years of age.
The 3rd. most productive stage is from 50 to 60 years of age.
in NEW ENGLAND JOURNAL OF MEDICINE