Letters of Alexander von Humboldt to Varnhagen von Ense. From 1827 to 1858. With extracts from Varnhagen's diaries, and letters of Varnhagen and others to Humboldt
Humboldt, Alexander von, 1769-1859; Varnhagen von Ense, Karl August, 1785-1858; Kapp, Friedrich, 1824-1884; Assing, Ludmilla, d. 1880