1. BEAUVIERIE , J. 1925 Bull. Soc. Botan. de France. Vine ser. , 1 , 1012 .
2. BOLTJEs T. 1934 Onderzoekingen over Nitrificeerende Bacterien. Thesis Techn. Hoogeschool Delft.
3. BUCHANAN R. 1925 General Systematic Bacteriology. Williams & Wilkins Baltimore.
4. CHOLODNY N. 1926 Die Eisenbakterien. Gustav Fischer Jena.
5. Jour;DAVIS D.;Infect. Dis.,1919