1. A study of Environmental Factors in Harrison's Cave, Barbados, West Indies 24 July- 1 August 1994
by HOBBS, HORTON H., III, Editor 
Price: USD 35.00
Dealer: Abebooks, Reader's Corner, Inc.
Description: ISBN10: 1879961318, ISBN13: 9781879961319, [publisher: National Speleological Fountation] Softcover First Edition This is a fine first edition paperback copy, plain white spine. MEDIA SHIPPING ONLY, extra for airmail or international shipping. [Raleigh, NC, U.S.A.] [Publication Year: 1994]  

2. Caves of Fire: Inside America's Lava Tubes
by Dave Bunnell 
Price: USD 35.00
Dealer: Abebooks, Reader's Corner, Inc.
Description: ISBN10: 1879961318, ISBN13: 9781879961319, [publisher: National Speleological Society] Softcover First Edition This is a fine first edition paperback copy, black spine. MEDIA SHIPPING ONLY, extra for airmail or international shipping. [Raleigh, NC, U.S.A.] [Publication Year: 2008]