Does someone have a titles for number 15 and 16 of the history AG Mysteries?

The History Mysteries are

1. The Smugglers's Treaure
2. Hoofbeats of Danger
3. The night Flyers

4. Voices at Whisper bend
5. Secrets on 26th Street
6. Mystery of the Dark Tower

7. Trouble at Fort La Pointe
8. Under Copp's Hill
9. Watcher in the Piney Woods

10. Shadows in the Glasshouse
11. The Minstrel's Melody
12. Riddle of the Prairie Bride

13. Enem;y in the Fort
14. Circle of Fire
15. ?

16. ?
17. Mystery at Chikoot Pass
18. The Strange Case of Baby H
19. Danger at the Wild West Show
20. Gangsters at the Grand Altantic
21. Ghost Lite on Graveys Shoal
22. Betrayal at Cross Creek