TY  - BOOK
AU  -  Helgeson,Earl Adrian
TI  -  Methods of weed control
T2  -  FAO agricultural studies ; 
PY  - 1957///
CY  -  Rome : 
PB  -  Food and Agriculture Organization of the United Nations, 
KW  -  Weeds
KW  -  Control
N1  -  Includes bibliographical references (p. 155-158)
ER  -