Medea

Medea was a person in Greek Mythology.

The Sea of Monsters
In The Sea of Monsters, Annabeth mentions Medea's Sunscreen.

The Titan's Curse
In The Titan's Curse, Dionysus mentions her while talking to Percy.

The Demigod Files
In a diagram of Annabeth's Camp Trunk, there is Medea's SPF 5000 sunscreen.

The Lost Hero
Jason, Piper and Leo come to her mall, leave her for dead and rescue Coach Hedge.

Aphrodite is later shown there in a dream vision to Piper, looking at clothes.