SOIL. Soil taxonomy: A basic system of soil classificationfor making and interpreting soil surveys. Departement of Agriculture.
Lua i Stíl Chicago (17ú heag.)SOIL. Soil Taxonomy: A Basic System of Soil Classificationfor Making and Interpreting Soil Surveys. U.S: Departement of Agriculture.
Lua MLA (9ú heag.)SOIL. Soil Taxonomy: A Basic System of Soil Classificationfor Making and Interpreting Soil Surveys. Departement of Agriculture.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.