- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
With reference to Wenlockian and Ludlovian (Silurian) lithologies of the Howgill Fells, northern England, described by R. B. Rickards (for reference, see this Bibliography Vol. 30), exception is taken to the conclusion that the Wenlockian graptolitic mudstones are pelleted and otherwise reworked. Comparisons with similar occurrences in the Lake District (England) are cited as evidence.