Boyd, James I. C. (1985). Narrow Gauge Railways in North Caernarvonshire, Volume 2: The Penrhyn Quarry Railways. Usk: The Oakwood Press. ISBN 978-0-85361-312-1. OL 8284743M. The British Narrow Gauge Railway No. 5.
Boyd, James I. C. (1985). Narrow Gauge Railways in North Caernarvonshire, Volume 2: The Penrhyn Quarry Railways. Usk: The Oakwood Press. ISBN 978-0-85361-312-1. OL 8284743M. The British Narrow Gauge Railway No. 5.