Clackamas Community College
Clackamas Community College: Citric Acid Cycle
This is a great site on the citric acid (Krebs) cycle. Each step of the cycle is written in easy-to-understand language, accompanied with diagrams.
Kent State University
Kent State University: Krebs Cycle
This page contains diagrams and formulas for the Krebs cycle. The page has seven different catagories. The page is written by Clarke Earley, Ph.D., a chemistry professor at Kent State University.