WALKER, R. (2005). Under the microscope the human body volume 1 heart: How the blood gets around the body. Grolier Educational.
Chicago-viite (17. p.)WALKER, Richard. Under the Microscope the Human Body Volume 1 Heart: How the Blood Gets Around the Body. Danbury: Grolier Educational, 2005.
MLA-viite (9. p.)WALKER, Richard. Under the Microscope the Human Body Volume 1 Heart: How the Blood Gets Around the Body. Grolier Educational, 2005.
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