"Lousma: 13, we've got one more item for you, when you get a chance. We'd like you to stir up your cryo tanks. In addition, I have shaft and trunnion – – Swigert: Okay. Lousma: – – for looking at the Comet Bennett, if you need it. Swigert: Okay. Stand by. [two minutes of silence] Swigert: Okay, Houston, we've had a problem here. Lousma: This is Houston. Say again, please. Lovell: Uh, Houston, we've had a problem. We've had a MAIN B BUS UNDERVOLT. Lousma: Roger. MAIN B UNDERVOLT. Lousma: Okay, stand by, 13. We're looking at it."