Mwngloddiau gadawedig a'r amgylchedd dŵr /
Johnston, Dave.
Great Britain.Environment Agency.
Scottish Environment Protection Agency.
Great Britain.Coal Authority.
Bristol : Environment Agency,
2008.
"Adroddiad gwyddoniaeth SC02013641".
"Product code: SCHO0508BNZU-B-P".
Includes bibliographical references.