Sorry to be pedantic but little, if any, of the Lincolnshire material, in the books edited by Patrick O'Shaughnessy and cited above, was collected by 'R.V.Williams' (I've done a quick scan but have failed to find a mention of his name). The majority of the songs printed in these two books were collected by Percy Grainger. Apart from Grainger a few other Twentieth Century Lincolnshire collectors are represented.