Chemistry LibreTexts - The Citric Acid Cycle
Basic introduction identifying the most important features of the Krebs Cycle.
Biology LibreTexts - Citric Acid (Krebs) CycleTours the pathway step-by-step. This is one of the metabolic pathways where you really do want to go into the MCAT knowing the individual enzymes and what happens in each step.
Lumen Learning - The Citric Acid (Krebs) CycleConcise tour of the stages of the cycle.