H. Jabran Zahid, Erick Robinson, Robert L. Kelly: Agriculture, population growth, and statistical analysis of the radiocarbon record. Proceedings of the National Academy of Sciences, 22.12.2015, nro 4, s. 931–935. doi:10.1073/pnas.1517650112ISSN 0027-8424Artikkelin verkkoversio. (englanti)
Nutritional and greenhouse gas impacts of removing animals from US agriculture. Proceedings of the National Academy of Sciences, 13.11.2017, 114. vsk, nro 48. doi:10.1073/pnas.1707322114Artikkelin verkkoversio.
H. Jabran Zahid, Erick Robinson, Robert L. Kelly: Agriculture, population growth, and statistical analysis of the radiocarbon record. Proceedings of the National Academy of Sciences, 22.12.2015, nro 4, s. 931–935. doi:10.1073/pnas.1517650112ISSN 0027-8424Artikkelin verkkoversio. (englanti)
Nutritional and greenhouse gas impacts of removing animals from US agriculture. Proceedings of the National Academy of Sciences, 13.11.2017, 114. vsk, nro 48. doi:10.1073/pnas.1707322114Artikkelin verkkoversio.
H. Jabran Zahid, Erick Robinson, Robert L. Kelly: Agriculture, population growth, and statistical analysis of the radiocarbon record. Proceedings of the National Academy of Sciences, 22.12.2015, nro 4, s. 931–935. doi:10.1073/pnas.1517650112ISSN 0027-8424Artikkelin verkkoversio. (englanti)