Sir Kyffin Williams R.A. (British, 1918-2006) Cwm Idwal, signed with initials 'KW.' (lower right); titled 'Cwm Idwal' (on sheet verso), pencil and watercolour on paper, 39 x 39cm (15 3/8 x 15 3/8in). with a further pencil sketch of a landscape on the reverse, by the same hand