Boat Seen Sailing up in the Clouds (sources)
- The Shell Guide to Wales, by Alun Llewellyn & Wynford Vaughan-Thomas, 1969. Pgs. 190-191
- Y Cymmrodor, Vol. 49, Part 1, 1947 The Honourable Society of Cymmrodorion, London, England. pg. 239. Online at: http://books.google.com/books?ei=T7J7VKvSEIWrjAKW34GYCw&id=EigrAAAAIAAJ&dq=%22Y+Cymmrodor%22+1947&focus=searchwithinvolume&q=%22Ready+money%2C+Lands%2C+Bonds%2C+or+Cattle+which%22
Mentions
- Phenomena: a Book of Wonders, by John Michell & Robert J.M. Rickard, 1977 Pantheon Books, New York, USA. ISBN: 0-394-73389-4. Pgs. 64