APA   Click to copy
Polechová, J., & Barton, N. H. (2015). Limits to adaptation along environmental gradients. Proceedings of the National Academy of Sciences of the United States of America, 112, 6401–6406. https://doi.org/10.1073/pnas.1421515112

Chicago/Turabian   Click to copy
Polechová, J, and NH Barton. “Limits to Adaptation along Environmental Gradients.” Proceedings of the National Academy of Sciences of the United States of America 112 (2015): 6401–6406.

MLA   Click to copy
Polechová, J., and N. H. Barton. “Limits to Adaptation along Environmental Gradients.” Proceedings of the National Academy of Sciences of the United States of America, vol. 112, National Academy of Sciences, 2015, pp. 6401–06, doi:10.1073/pnas.1421515112.

@article{polechov2015a,
  title = {Limits to adaptation along environmental gradients},
  year = {2015},
  journal = {Proceedings of the National Academy of Sciences of the United States of America},
  pages = {6401--6406},
  publisher = {National Academy of Sciences},
  volume = {112},
  doi = {10.1073/pnas.1421515112},
  author = {Polechová, J and Barton, NH}
}