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Paleozoic species of Vetacapsula and Palaeoxyris. Summary of progress of the Geological Survey of Great Britain and the Museum of Practical Geology for 1927, part II: 87–108
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The nature and affi nities of Palaeoxyris, etc. Summary of progress of the Geological Survey of Great Britain and the Museum of Practical Geology for 1931, part II: 122–140