Template:Ref-DorlandBartelmez1922
From Embryology
Dorland WAN. and Bartelmez GW. Clinical and embryologic report of an extremely early tubal pregnancy; together with a study of decidual reaction, intra-uterine and ectopic. (1922) Amer. J. Obst. Gynecol, 4: 215-227 and 4:372-386.