https://en.wikipedia.org/wiki/Bletherston
https://www.genuki.org.uk/big/wal/PEM/Bletherston
GB Historical GIS / University of Portsmouth, History of Bletherston in Pembrokeshire | Map and description, A Vision of Britain through Time.
http://www.visionofbritain.org.uk/place/4546
https://maps.nls.uk/geo/explore/print/#zoom=14.26&lat=51.8663&lon=-4.7804&layers=171&b=1