1. The role of microorganism metabolites in the formation of humus substances;Alexandrova;Pochvovedenie,1968
2. On the technique of humus substance extraction from humifying plant residues;Alexandrova;Pochvovedenie,1972
3. Humus formation processes in the soil;Alexandrova,1970
4. Humusstoffe;Flaig,1966
5. Über die Beteilung von Phenolen am Aufbau von Huminsäuren;Flaig,1968