Helland, P. E.; Holmes, M. A. (1997): Surface textural analysis of quartz sand grains from ODP Site 918 off the southeast coast of Greenland suggests glaciation of southern Greenland at 11Ma.. Elsevier, Amsterdam, Netherlands, Palaeogeography, Palaeoclimatology, Palaeoecology, 135 (1-4), 109-121, georefid:1998-021223