1. Azimi, P.H., Cramblett, H.G. and Haynes, R.E. J.A.M.A. 207: 509–512, 1969.
2. Bang, H.O. and Bang, J. Acta Med. Scand. 113: 487–505, 1943.
3. Beard, CM., Benson, R.C., Kelalis, P.P., Eveback, L.R. and Kurland, L.T. Mayo Clinic Proc. 52: 3–7, 1977.
4. Bernard, J.P. and Northrop, R.L. J. Virol. 14: 183–186, 1974.
5. Bistrian, B., Phillips, C.A. and Kaye, I.S. J.A.M.A. 222: 478–479. 1972.