1. Twins and heredity;Bender;Practitioner, Lond.,1959
2. The heritability of certain anthropometrie characters as ascertained from measurements of twins;Clark;Amer. J. Human Genet.,1956
3. The genesis of twins;Fisher;Genet.,1919
4. Factors influencing appearance of centers of ossification during early childhood;Francis;Amer. J. Dis. Child.,1939