1. F. Haber , The synthesis of ammonia from its elements – Nobel Lecture for 1918 Prize, https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1918/haber-lecture.html
2. H. Hildebrandt , Presentation speech for the 1909 Nobel Prize in Chemistry, https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1909/press.html
3. W. Pauli , “God made the bulk; the surface was invented by the devil”, quoted in Growth, Dissolution, and Pattern Formation in Geosystems (1999) by Bjørn Jamtveit and Paul Meakin, p. 1291
4. The role of potassium in the catalytic synthesis of ammonia
5. Interactions of potassium, oxygen and nitrogen with polycrystalline iron surfaces