S.B. Wolbach and M.J. Schlesinger, 'The Cultivation of the Micro-Organisms of Rocky Mountain spotted Fever (Dermacentroxenus Rickettsi) and of Typhus (Rickettsia Prowazeki) in Tissue Cultures,' The Journal of Medical Research 44 (2) (1923), pp. 231-256.
S.B. Wolbach and M.J. Schlesinger, 'The Cultivation of the Micro-Organisms of Rocky Mountain spotted Fever (Dermacentroxenus Rickettsi) and of Typhus (Rickettsia Prowazeki) in Tissue Cultures,' The Journal of Medical Research 44 (2) (1923), pp. 231-256.