Activity in the octogenarian: a study of fourteen Spanish-American war veterans.
D000368:Aged; D006787:Hospitals, Veterans; D006801:Humans; D008136:Longevity; D008297:Male; D008404:Massachusetts; D010044:Outpatient Clinics, Hospital; D010415:Pensions; D012179:Retirement; D012924:Social Conditions; D012943:Social Security