Dominic Woolf, James E. Amonette, F. Alayne Street-Perrott, Johannes Lehmann, Stephen Joseph; Amonette; Street-Perrott; Lehmann; Joseph (August 2010). «Sustainable biochar to mitigate global climate change». Nature Communications1 (5): 1-9. Bibcode:2010NatCo...1E..56W. ISSN2041-1723. doi:10.1038/ncomms1053.
Lehmann, Johannes. «Terra Preta de Indio». Soil Biochemistry (internal citations omitted). Not only do biochar-enriched soils contain more carbon - 150gC/kg compared to 20-30gC/kg in surrounding soils - but biochar-enriched soils are, on average, more than twice as deep as surrounding soils.[citarequerida]
Dominic Woolf, James E. Amonette, F. Alayne Street-Perrott, Johannes Lehmann, Stephen Joseph; Amonette; Street-Perrott; Lehmann; Joseph (August 2010). «Sustainable biochar to mitigate global climate change». Nature Communications1 (5): 1-9. Bibcode:2010NatCo...1E..56W. ISSN2041-1723. doi:10.1038/ncomms1053.
Dominic Woolf, James E. Amonette, F. Alayne Street-Perrott, Johannes Lehmann, Stephen Joseph; Amonette; Street-Perrott; Lehmann; Joseph (August 2010). «Sustainable biochar to mitigate global climate change». Nature Communications1 (5): 1-9. Bibcode:2010NatCo...1E..56W. ISSN2041-1723. doi:10.1038/ncomms1053.