'Cafodd Arup ei gomisiynu gan bartneriaeth yn cynnwys awdurdodau parciau cenedlaethol Cymru, Cyfoeth Naturiol Cymru a Chymdeithas Llywodraeth Leol Cymru i ystyried gwerth economaidd parciau cenedlaethol Cymru' = 'Arup was commissioned by a partnership of the Welsh national park authorities, Natural Resources Wales and the Welsh Local Government Association to consider the economic value of Wales' national parks.'
Rhoi gwerth ar barciau cenedlaethol Cymru. Published by Arup in 2013. Publication and catalogue information, links to buy online and reader comments.