Herrero et al. (2011)
Also: Herrero et al. 2011
Livestock and greenhouse gas emissions: The importance of getting the numbers right
Herrero, M., Gerber, P., Vellinga, T., Garnett, T., Leip, A., Opio, C., ... & McAllister, T. A. (2011). Livestock and greenhouse gas emissions: The importance of getting the numbers right. Animal Feed Science and Technology, 166, 779-782. Link to paper
https://doi.org/10.1016/j.anifeedsci.2011.04.083
References
All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.