Wachter R F, Briggs G P, Pedersen C E
Infect Immun. 1977 Feb;15(2):668-9. doi: 10.1128/iai.15.2.668-669.1977.
The pronounced change in the buoyant density of Coxiella burnetii in CsCl gradients that was caused by treatment with formalin or ultraviolet radiation was not observed with Rickettsia rickettsii.