* {{cite book | last=Hall | first=John Edward | last2=Guyton | first2=Arthur C. | title=Guyton and Hall Textbook of Medical Physiology | publisher=Saunders | publication-place=Philadelphia, Pa | date=2011 | isbn=978-1-4160-4574-8}}
<ref name="k125">{{cite book | last=Hall | first=John Edward | last2=Guyton | first2=Arthur C. | title=Guyton and Hall Textbook of Medical Physiology | publisher=Saunders | publication-place=Philadelphia, Pa | date=2011 | isbn=978-1-4160-4574-8 | page=}}</ref>