Longevity of First Ladies of the United States.
D005197:Famous Persons; D005260:Female; D006076:Government; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D008136:Longevity; D008393:Marriage; D011057:Politics; D014481:United States