This image was include as an example of the ray tracing
technique in an expository article about Computer Graphics
for Ciencia Hoje.
The cover image is also from the same article.
Distributed ray tracing
software developed by the author for Fantastic Animation
Machine Inc, a computer animation production company.
Jonas Gomes and Luiz Velho,
Ciência Hoje, 10(56):36-47, Agosto 1989. SBPC.
Ciência Hoje, Volume 10, Number 56, August 1989.