The Wenlock graptolites of the Ludlow district, Shropshire, and their stratigraphical significance

12 4 December 663 683

HOLLAND, C. H., RICKARDS, R. B., WARREN, P. T. 1969. The Wenlock graptolites of the Ludlow district, Shropshire, and their stratigraphical significance. Palaeontology12, 4, 663–683.

C. H. Holland, R. B. Rickards and P. T. Warren The Palaeontological Association (Free Access)