● Eggerth AH,Gagnon BH (1933). The Bacteroides of Human Feces.
J. Bacteriol. 25, 389-413.
● Bergan T,Hovig B (1968). A new species, Sphaerophorus intermedius, isolated from empyema.
Acta Pathol Microbiol Scand 74, 421-30.
● Krasil’nikov NA (1949). Guide to the bacteria and actinomycetes. Edition: , Moskva-Leningrad: Izdatel''stvo Akademii Nauk SSSR.
● Veillon A,Zuber A (1898). Recherches sur quelques microbes strictement anaérobies et leur rôle en pathologie.
Arch. Méd. Expt. et Anat. Path. 10, 517-545.
● Castellani A,Chalmers AJ (1919). Manual of Tropical Medicine. Edition: 3, New York: Williams Wood and Co..
● Prévot AR (1938). Études de systématique bactérienne.
Ann. Inst. Pasteur (Paris) 60, 285-307.
● Topley WWC,Wilson GS (1929). The principles of Bacteriology and Immunity. Edition: 1, London: Edward Arnold and Co..