Callahan, D. (1990). What kind of life: The limits of medical progress. Simon and Schuster.
Chicago-viite (17. p.)Callahan, Daniel. What Kind of Life: The Limits of Medical Progress. Simon and Schuster, 1990.
MLA-viite (9. p.)Callahan, Daniel. What Kind of Life: The Limits of Medical Progress. Simon and Schuster, 1990.
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