@article{
  author = {Alimohammadi, Mehrzad, valadabadi, seed alireza, daneshiyan, jahanfar, aref, behruz},
  title = {Effects of nitrogen and planting density on yield and oil content of castor (Ricinus communis L.)},
  journal = {Agroecology Journal},
  year = {2011},
  volume = {6},
  number = {4},
  pages = {57-65},
  doi = {}
}