1. Allen, R.J. 2002, in Seeing Through the Dust, eds. A.R. Taylor, T.L. Landecker, and A.G. Willis (ASP Conference Series, Vol. 276 ), 288
2. Allen, R.J., Goss, W.M, and Van Woerden, H. 1973, AandA, 29, 447 748
3. Allen, R.J., Atherton, P. D., and Tilanus, R. P. J. 1986, Nature, 319, 296
4. Allen, R.J., Knapen, J. H., Bohlin, R., and Stecher, T. P. 1997, ApJ, 487, 171
5. Allen, R.J., Heaton, H.I., and Kaufman, M.J. 2004, ApJ, 608, 314.