Works Used
Constam, Daniel. 2002. Axis formationand germ layer specification in the mammalian embryo. ISREG Scientific Report. Jan. 2002: 22-24.
Mouse Atlas Project. Baldock, R., J. Bard, D, Davidson, and K. Lawson. 1998. EMAP. 21 March 2004.
http://genex.hgu.mrc.ac.uk/CDROM_online/macd/html_shdw_links/mastaging.html
Gilbert, Scott. 2003. Developmental Biology, 7th ed. Sinauer Associates, Inc., MA, pp. 368-376.
Staveley, Dr. Brian E. Developmental Biology (Biol3530). 3 March 2004. Department of Biology, Memorial University of Newfoundland.
Wells, J., and D. A. Melton. 1999. Vertebrate Endoderm Development. Annual review of Cell and Developmental Biology. 15: 393-410.