J.A. Movshon, I.D. Thompson, and D.J. Tolhurst, "Spatial summation in the receptive fields of simple cells in the cat's striate cortex," Journal of Physiology, 283, pp. 53-77, 1978.
 J.P. Jones and L.A. Palmer, "An evaluation of the two-dimensional Gabor filter model of simple receptive fields in cat striate cortex," Journal of Neurophysiology, vol. 58, pp. 1233-1258, 1987.
 D.H. Hubel and T.N. Wiesel, "Ferrier lecture: functional architecture of Macaque monkey visual cortex," Proceedings of the Royal Society of London, Series B, vol. 198, pp. 1-59, 1977.
 W.T. Freeman and E.H. Adelson, "The design and use of steerable filters," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 13, pp. 891-906, 1991.
 T.C. Folsom, Neural Networks Modeling Cortical Cells for Machine Vision, Ph.D. Dissertation, University of Washington, Seattle, Washington, 1994
 T.C. Folsom and R.B Pinter, "Primitive features from steering, quadrature and scale," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 20, no. 11, November 1998