Columbia subject headings:
Authors, American--19th century--Biography.
Twain, Mark, 1835-1910--Bibliography.
Twain, Mark, 1835-1910.
Harvard subject headings:
Authors, American--19th century--Biography
Twain, Mark, 1835-1910
Twain, Mark, 1835-1910--Bibliography.
Princeton subject headings:
Authors, American--19th century--Biography.
Twain, Mark, 1835-1910--Bibliography.
Twain, Mark, 1835-1910.