Rujukan Usus

  1. ↑ Maton, Anthea (1993). Human Biology and Health. Englewood Cliffs, New Jersey, USA: Prentice Hall. ISBN 0-13-981176-1.  Parameter |coauthors= tidak diketahui diabaikan (guna |author=) (bantuan)
  2. ↑ Thomasin.shtml "Length of a Human Intestine" Check |url= value (bantuan). Dicapai 2 September 2009.