Transactions of the Royal Geological Society of Cornwall, Vol.6 p334 - 347
| On an important slate term in the Killas Series of Cornwall & South Devon, not sufficiently adverted to in my former classification of that group as communicated to the Society in 1943, with additional proofs in confirmation of the true Geological position of the Ocrynian or Devonian system, Rev D Williams, VI: 334-347, 1846. |