Columbia subject headings:
Fabre, Jean-Henri, 1823-1915.
Humboldt, Alexander von, 1769-1859.
Mathematicians--France.
Mathematics--Study and teaching.
Harvard subject headings:
Fabre, Jean-Henri, 1823-1915.
Humboldt, Alexander von, 1769-1859.
Mathematicians--France.
Mathematics--Study and teaching
Textbooks--United States.
Princeton subject headings: