Columbia subject headings:
Harvard subject headings:
Education
Education--Philosophy
Geometry--Study and teaching
Ostrogorskiĭ, A. N. (Alekseĭ Nikolaevich), 1840-1917.
Princeton subject headings:
Education--Philosophy.
Education.
Geometry--Study and teaching.
Ostrogorskiĭ, A. N. (Alekseĭ Nikolaevich), 1840-1917.