Here are the references formatted in BibTeX style:
```bibtex
@article{shalem2014,
author = {O. Shalem and N. E. Sanjana and E. Hartenian and X. Shi and D. A. Scott and T. Mikkelson and D. Heckl and B. L. Ebert and D. E. Root and J. G. Doench and F. Zhang},
title = {Genome-scale CRISPR-Cas9 knockout screening in human cells},
journal = {Science},
year = {2014},
volume = {343},
pages = {84--87},
doi = {CrossRef},
note =