Tham khảo Thủy_tức

  • Chang, T.D. and Sullivan, J.M. "Temporal associations of coral and zooplankton activity on a Caribbean reef" Dartmouth Studies in Tropical Ecology. 2008. Truy cập 2009-06-21.
  • Chisholm, Hugh, ed (1911). "Polyp". Encyclopædia Britannica (Eleventh ed.). Cambridge University Press. http://encyclopedia.jrank.org/PIG_POL/POLYP.html.