@misc{atk2011the,
  title = {The vegetation of Singapore ―an updated map}
  author = {A.T.K. Yee, Richard T. Corlett
, S.C. Liew
 and Hugh T.W. Tan},
  url = {https://pdfs.semanticscholar.org/b0d3/e53dc66ec309d5fb5607098e262ed60564fe.pdf},
  year = {2011}
}