Magic Knight Rayearth Vol 3

From the Tokyopop edition

The end of the adventure is at hand for Hikaru, Umi, and Fuu, three schoolgirls from Tokyo who were transported to the magical realm of Cephiro to become the Magic Knights. They have unlocked their magic, powered up their weapons, and defeated Zagato's minions. But one test remains before they can confront the sinister Zagato himself, and release the imprisoned Princess Emeraude. They must don the three Mashin - powerful spirits that can only be wielded by Magic Knights. With the girls' magic fully charged, the final battle begins!

Source: Anime News Network Encyclopedia