--- ray/doc/ray.1	2011/06/21 23:58:00	1.20
+++ ray/doc/ray.1	2016/05/25 18:52:45	1.29
@@ -1,8 +1,8 @@
-.\" RCSid "$Id"
+.\" RCSid "$Id: ray.1,v 1.29 2016/05/25 18:52:45 greg Exp $"
 .\" Print using the -ms macro package
-.DA 2/17/2011
+.DA 09/18/2015
 .LP
-.tl """Copyright \(co 2011 Regents, University of California
+.tl """Copyright \(co 2015 Regents, University of California
 .sp 2
 .TL
 The
@@ -899,9 +899,7 @@ a parallel BSDF surface may be
 placed slightly less than the given thickness away from the front surface
 to enclose the complex geometry on both sides.
 The sign of the thickness is important, as it indicates whether the
-proxied geometry is behind the.
-.I BSDF
-surface (when thickness is positive)
+proxied geometry is behind the BSDF surface (when thickness is positive)
 or in front (when thickness is negative).
 .LP
 The second string argument is the name of the BSDF file, which is
@@ -1157,6 +1155,7 @@ between 0.1 (for tightly spaced characters) and 0.3 (f
 Mixtures
 .PP
 A mixture is a blend of one or more materials or textures and patterns.
+Blended materials should not be light source types or virtual source types.
 The basic types are given below.
 .LP
 .UL Mixfunc
@@ -1553,6 +1552,25 @@ the Ecole Polytechnique Federale de Lausanne (EPFL Uni
 in Lausanne, Switzerland.
 .NH 1
 References
+.LP
+Ward, G., M. Kurt & N. Bonneel,
+``Reducing Anisotropic BSDF Measurement to Common Practice,''
+.I Workshop on Material Appearance Modeling,
+2014.
+.LP
+McNeil, A., C.J. Jonsson, D. Appelfeld, G. Ward, E.S. Lee,
+``A validation of a ray-tracing tool used to generate
+bi-directional scattering distribution functions for
+complex fenestration systems,''
+.I "Solar Energy",
+98, 404-14, November 2013.
+.LP
+Ward, G., R. Mistrick, E.S. Lee, A. McNeil, J. Jonsson,
+``Simulating the Daylight Performance of Complex Fenestration Systems
+Using Bidirectional Scattering Distribution Functions within Radiance,''
+.I "Leukos",
+7(4),
+April 2011.
 .LP
 Cater, K., A. Chalmers, G. Ward,
 ``Detail to Attention: Exploiting Visual Tasks for Selective Rendering,''