APA   Click to copy
Koren, Y., Bell, R., & Volinsky, C. (2009). Matrix factorization techniques for recommender systems. Computer, 42, 30–37.

Chicago/Turabian   Click to copy
Koren, Yehuda, Robert Bell, and Chris Volinsky. “Matrix Factorization Techniques for Recommender Systems.” Computer 42 (2009): 30–37.

MLA   Click to copy
Koren, Yehuda, et al. “Matrix Factorization Techniques for Recommender Systems.” Computer, vol. 42, IEEE, 2009, pp. 30–37.

@article{koren2009a,
  title = {Matrix factorization techniques for recommender systems},
  year = {2009},
  journal = {Computer},
  pages = {30--37},
  publisher = {IEEE},
  volume = {42},
  author = {Koren, Yehuda and Bell, Robert and Volinsky, Chris}
}