Columbia subject headings:
Harvard subject headings:
Monarchy--Austria--History.
Monarchy--Hungary--History.
Rudolf, Crown Prince of Austria, 1858-1889
Österreichisch-ungarische Monarchie in Wort und Bild.
Princeton subject headings:
Rudolf, Crown Prince of Austria, 1858-1889. Österreich-ungarischen Monarchie in Wort und Bild.