Columbia subject headings:
Harvard subject headings:
Chemists--Germany--Correspondence.
Liebig, Justus, Freiherr von, 1803-1873--Correspondence.
Otto, Friedrich Julius, 1809-1870--Correspondence.
Pharmacologists--Germany (West)--Correspondence.
Pharmacology--Germany--Braunschweig--History.
Princeton subject headings:
Chemists--Germany--Correspondence.
Liebig, Justus, Freiherr von, 1803-1873--Correspondence.
Otto, Friedrich Julius, 1809-1870--Correspondence.
Pharmacologists--Germany--Correspondence.
Pharmacology--Germany--Braunschweig--History.