@article{he_cattelan_kirovski_2008, 
  title={Modeling viral economies for digital media}, 
  volume={42}, 
  DOI={10.1145/1357010.1352609}, 
  publisher={Association for Computing Machinery (ACM)}, 
  author={He and Cattelan and Kirovski}, 
  year={2008}, 
  month={Apr}
  }