Text recommendations?

Hi all. What texts besides Powers would you recommend to an interested
newcomer to Perceptual Control systems?

[From Bruce Gregory (970618.1010 EDT)]

Nandomark <nandomark@AOL.COM>

Hi all. What texts besides Powers would you recommend to an interested
newcomer to Perceptual Control systems?

Rick Marken's _Mind Readings_ is superb. Very clear and very
informative. Highly recommended.

Bruce