ISBN-13: 9783319658001 / Angielski / Twarda / 2017 / 411 str.
ISBN-13: 9783319658001 / Angielski / Twarda / 2017 / 411 str.
The focus of this book is on the more than 2000 caves of the Greenbrier Valley of West Virginia of which the 14 with lengths greater than 10 km have an aggregate length of 639 km.