N. E. Hahn HAHN, N. E., FLETCHER, M., RICE, R. M., KOCAN, K. M., HANSEN, J. W., HAIR, J. A., … PERRY, B. D. (1990). ATTEMPTED TRANSMISSION OF EHRLICHIA-RISTICII, CAUSATIVE AGENT OF POTOMAC HORSE FEVER, BY THE TICKS, DERMACENTOR-VARIABILIS, RHIPICEPHALUS-SANGUINEUS, IXODES-SCAPULARIS AND AMBLYOMMA-AMERICANUM. EXPERIMENTAL & APPLIED ACAROLOGY, 8(1-2), 41–50. https://doi.org/10.1007/BF01193380