"It is the product of a major conference to mark the centenary of the founding of the Folk-Song Society, held at the University of Sheffield, 10-12 July 1998"--p.1.
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Folk song : tradition, revival, and re-creation. ISBN 0954568206. Published by The Elphinstone Institute, University of Aberdeen in 2004. Publication and catalogue information, links to buy online and reader comments.
