TY - BOOK AU - Barbera,J.P.M. AU - Beddington,R.S.P. AU - Clements,M. AU - Kioussis,D. AU - Meloy,D. AU - Rodriguez,T. AU - Thomas,P. TI - The homeobox gene Hex Is required in definitive endodermal tissues for normal forebrain, liver and thyroid formation ER -