Gaya APA
Astera, M., Agricola, . (2014).
The Ideal Soil 2014: A Handbook for the New Agriculture .
s.l.:
SoilMinerals.com.
Gaya MLA
Astera, Michael., Agricola, .
"The Ideal Soil 2014: A Handbook for the New Agriculture".
s.l.:
SoilMinerals.com,
2014.
Computer File.