Wildside Press has been working to reissue many of his classic works. Here, then, are four of his action-adventure novels aimed at the Young Adult market (they are quite readable for adults, too):

Cave of Danger
Harpoon Gunner
Hurricane Reef
The Fire Trail

If you enjoy this ebook, don't forget to search your favorite ebook store for "Wildside Press Megapack" to see more of the 260+ volumes in this series, covering adventure, historical fiction, mysteries, westerns, ghost stories, science fiction -- and much, much more!