User blog comment:Darkcloud1111/''The Mark of Athena'' Plot Holes/@comment-66.177.180.197-20121213223148/@comment-3146930-20121223103539

I have to disagree. I ran a search on the word Gaia in all three of The Heroes of Olympus book and the spelling "Gaia" only appears once, in the Glossary of The Mark of Athena under the Titan's definition. All other spellings are Gaea.