Layman, C. A., Araujo, M. S., Boucek, R., Hammerschlag‐Peyer, C. M., Harrison, E., Jud, Z. R., ... & Bearhop, S. (2012). Applying stable isotopes to examine food‐web structure: an overview of analytical tools. Biological Reviews, 87(3), 545-562. https://doi.org/10.1111/j.1469-185X.2011.00208.x