3) Shishido, A.: Identification and serological classification of the causative agent of scrub typhus in Japan. Jap. J. Med. Sci. Biol., 15: 308-321, 1962.
4) Kobayashi, Y., Tachibana, N., Matsumoto, I., Oyama, T. & Kageyama, T.: Isolation of very low virulent strain of Rickettsia tsutsugamushi by the use of cyclophosphamide-treated mice. Rickettsia and Rickettsial Diseases, Proc. 2nd Intl. Symposium of Rickettsia and Rickettsial Disease, Publishing House of the Slovak Acad. Sci. Blatis Lava, 1978, p.181-188.
5) Tamura, A., Takahashi, K., Tsuruhara, T., Urakami, H., Miyamura, S., Sekikawa, H., Kenmotsu, M., Shibata, M., Abe, S. & Nezu, H.: Isolation of Rickettsia tsutsugamushi antigenically different from Kato, Karp, and Gilliam strains from patients. Microbiol. Immunol., 26: 321-328, 1982.