Krug, R. (1998). Usmle step 1 Review Series: Behavioral Sciences U S Health Care Biostatistics & Epidemiology. s.n.
Chicago-viite (17. p.)Krug, Ronald. Usmle Step 1 Review Series: Behavioral Sciences U S Health Care Biostatistics & Epidemiology. Chicago: s.n, 1998.
MLA-viite (9. p.)Krug, Ronald. Usmle Step 1 Review Series: Behavioral Sciences U S Health Care Biostatistics & Epidemiology. s.n, 1998.
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