what view/table will show me what view columsn belong to which table columns?

I have a very complexed view that retrieves information from several tables, and I need to know what table columns these view columns are referencing, for example:

create sds_test (sds_num number, sds_data varchar2(50);
create sds_view (test_num,test_data) as (select sds_num,sds_data from sds_test);

How can I find out what table column test_num on the view sds_view is referencing, i.e. result would be sds_num on the table sds_test.

Thanks. Regards, Sheryl