links

http://www.renderman.org/RMR/Shaders/surface.html
http://www.3d.sk/
http://www.the-blueprints.com/
http://www.martian-labs.com/martiantoolz/products.php?product=rmshaders
https://renderman.pixar.com/products/tools/rps.html
http://www.textures.es3dstudios.com/blueprint/blueprint_01.html