Countryside Survey 1984 mapped estimates of linear feature lengths in Great Britain - Barr, C.J.; Bunce, R.G.H.; Maskell, L.C.; Norton, L.R.; Scott, R.J.; Scott, W.A.; Smart, S.M.; Stuart, R.C.; Whittaker, H.A.; Wood, C.M.; Wright, S.M. (NERC Environmental Information Data Centre, 2014)