Öberg, Å. N., Lindmark, G. E., Israelsson, A. C., Hammarström, S. G., Hammarström, M.-L. Detection of occult tumour cells in lymph nodes of colorectal cancer patients using real-time quantitative RT-PCR for CEA and CK20 mRNAs. Int. J. Cancer. 2004; 111(1): 101-110. DOI: 10.1002/ijc.20231.