8Gold P, Freedman SO. Specific carcinoembryonic antigens of the human digestive system. J Exp Med 1965; 122:467-481
9Nystrom JS, Dyce B, Wada J, Bateman JR, Haverback B. Carcinoembryonic antigen titers on effusion fluid. A diagnostic tool? Arch Intern Med 1977; 137:875-879
10Trape J, Molina R, Sant F. Clinical evaluation of the simultaneous determination of tumor markers in fluid and serum and their ratio in the differential diagnosis of serous effusions. Tumour Biol 2004; 25: 276-281
