This is an article by Frank Dietrich and presented at SIGGRAPH’84 and published in IEEE Computer Graphics and Applications, then the most important journal on the fledging art of Computer Graphics technology.

Long out of print and not easily accessable anywhere Frank pulled it out of storage, scanned it, and created an Acrobat pdf.

Inspite of being an old article, it still contains good info and an extensive list of references.

Read it (size: 3.2MB).