British Doctors Study

study (1951 to 2001) into smoking and lung cancer

en-GB/ˈbɹɪtɪʃ ˈdɒktəz stʌdiː/
en-US/ˈbɹɪdɪʃ ˈdɑktɚz ˈstʌdi/

دسته بندی ها:

cohort study