1. AMA diagnostic and treatment guidelines concerning child abuse and neglect;Council on Scientific Affairs;JAMA,1985
2. Increased child abuse in families with twins;Groothuis;Pediatrics,1982
3. Increased child abuse in twins;Nelson;Child Abuse Negl,1985
4. A study on child abuse in twins;Kobaykashi;J Jpn Pediatric Soc,1989
5. Frequency of multiple birth in three cities of Japan;Inouye;Am J Hum Genet,1957