Letter from Robert Dale Owen to David Thomas, 16 January 1859 Math Eitemau Uwchlwytho gan Llyfrgell Genedlaethol Cymru / The National Library of Wales
Letter from Robert Dale Owen to David Thomas, 12 March 1859 Math Eitemau Uwchlwytho gan Llyfrgell Genedlaethol Cymru / The National Library of Wales
Letter from Robert Dale Owen to David Thomas, 16 January 1859 Math Eitemau Uwchlwytho gan Llyfrgell Genedlaethol Cymru / The National Library of Wales
Letter from Robert Dale Owen to David Thomas, 14 February 1839 Math Eitemau Uwchlwytho gan Llyfrgell Genedlaethol Cymru / The National Library of Wales
Letter from Robert Dale Owen to David Thomas, 12 March 1859 Math Eitemau Uwchlwytho gan Llyfrgell Genedlaethol Cymru / The National Library of Wales
