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M.Bauma, A.Hackshawe, J.Houghtona, Rutqvistb, T.Fornanderb, B.Nordenskjoldc, A.Nicoluccid, R.Sainsburya, * ZIPP International Collaborators' Groupf

a Department of Surgery, University College London, Institute of Surgical Studies, 67–73 Riding House Street, Charles Bell House, London W1W 7EJ, United Kingdom;
b Stockholm Breast Cancer Study Group, Sweden;
c South-East Sweden Breast Cancer Group, Sweden;
d Gruppo Interdisciplinare Valutazione Interventi in Oncologia, Italy;
e Cancer Research UK & UCL Cancer Trials Centre, University College London, United Kingdom.