Rickettsia phylogenomics: unwinding the intricacies of obligate intracellular life. - Gillespie JJ; Williams K; Shukla M; Snyder EE; Nordberg EK; Ceraul SM; Dharmanolla C; Rainey D; Soneja J; Shallom JM; Vishnubhat ND; Wattam R; et al. (PloS one, 2008)