Template:Ref-Atwell1930
From Embryology
Atwell WJ. A human embryo with seventeen pairs of somites. Carnegie Instn. Wash. Publ. 407, Contrib. Embryol., 21: 1-24.
Atwell WJ. A human embryo with seventeen pairs of somites. Carnegie Instn. Wash. Publ. 407, Contrib. Embryol., 21: 1-24.