1. Webster’s revised unabridged dictionary,1913
2. Merriam-Webster’s collegiate dictionary,1998
3. Cytokeratin-positive cells in the bone marrow and survival of patients with stage I, II, or III breast cancer;Braun;N Engl J Med,2000
4. The right stuff;Wolfe,1983
5. Forgive and remember;Bosk,1979