Stephenson, J. (1931). Reports of an Expedition to Brazil and Paraguay in 1926-1927, supported by the Trustees of the Percy Sladen Memorial Fund and the Executive Committee of the Carnegie Trust for Scotland. The Oligochaeta. Journal of the Linnean Society of London, Zoology. 37(252): 291-326.
Reports of an Expedition to Brazil and Paraguay in 1926-1927, supported by the Trustees of the Percy Sladen Memorial Fund and the Executive Committee of the Carnegie Trust for Scotland. The Oligochaeta