• An enquiry into the truth of the tradition concerning the discovery of America by Prince Madog ab Owen Gwynedd about the year 1170 - John Williams - J Brown, London 1791.

• Farther observations on the discovery of America by Prince Madog ab Owen Gwynedd containing the account of a Welsh tribe or tribes of Indians now living in the western parts of North America - John Williams - J Brown, London 1792

• Reports in Archaeology and Anthropology Vol II - W S Webb and W D Funkhouser - University of Kentucky 1932 A paper contained therein deals with the archaeology of Jefferson County, Kentucky. The writers dwell at length on the battle between the Red and White Indians at the Falls of the Ohio

• MADOC ap Owain Gwynedd - Kathleen O'Loughlin - Ontario 1947

• Who discovered America? The amazing story of MADOC - Zella Armstrong - The Lookout Publishing Company 1950

• People of the First Man - Davis Thomas & Karin Ronnefeldt - E P Dutton

• Mandan and Hidatsa Villages in the Eighteenth and Nineteenth Centuries - Frank H Stewart - Plains Anthropologists, Part 1 1974 Whether it contains anything relevant to my research I don't know.

• Before Lewis and Clark - A P Nastair - St Louis 1952 (Two volumes)

• America BC - Barry Fell - 1970's

I know that there is a lot more information out there. Professor Gwyn Alf Williams in MADOC - The Legend of the Welsh Discovery of America lists three pages of 'Documentation' as source material.

I would appreciate it if people would send me any information regarding the legend, however tenuous it may appear, whether it is in the form of books, photographs, photocopies etc.

I am also interested in relevant books and information on the Vikings, St Brendan, the Princes of Gwynedd and the origins of the Indians.

I am seeking the truth and I stand to be corrected. As long as people supply me with evidence to support their claim, then I welcome all contributions, whether they are supportive or refute the story.