@article{
  author = {Hasanzadeh Aghbolaghi, Sakineh},
  title = {The effect of chemical control of Echinochloa crus- galli weed at different growth stages on oil seed sunflower
 (Helianthus annus  cv. Urofloure) yield.},
  journal = {Agroecology Journal},
  year = {2012},
  volume = {8},
  number = {3},
  pages = {13-21},
  doi = {}
}