1. Proliferation Marker Ki-67 in Early Breast Cancer
   Ander Urruticoechea et al, 2005, Journal of Clinical Oncology CrossRef
2. Comparison of the Systemic and Intratumoral Effects of Tamoxifen and the Aromatase Inhibitor Vorozole in Postmenopausal Patients With Primary Breast Cancer
   Catherine L. Harper-Wynne et al, 2002, Journal of Clinical Oncology CrossRef