[haertig]

I found Mediterranean Caper and Raise the Titanic in one of my libraries eBook offerings (I'm in the USA). They had Iceberg too, but that one was only available in Spanish. Then nothing, until Atlantis Found, which is book 15 of the series.

I have Deep Six and Sahara in paperback. I bought those some time ago, when they were still available on Amazon (I believe Sahara was used, Deep Six new). Deep Six is on my "already read" bookshelf, but darned if I can remember anything about it, even though I evidently read it at some time. I haven't tried to read Sahara yet, it's still on my "to be read" queue bookshelf, but I saw the movie.