TY  - BOOK
AU  - Penrose,L.S.
AU  - Berg,J.M.
AU  - Lang-Brown,Helen
TI  - The biology of mental defect / 
U1  - 157.8 
PY  - 1972///
CY  - London : 
PB  - Sigwick & Jackson, 
KW  - Mental deficiency
KW  - Mental illness
N1  -  Includes bibliographical references (p.297-338) and index
ER  -