Gaya APA
SURVICE, U, D, O, A, S, C. (1988).
Soil taxonomy: A basic of soil classification for making and interpreting soil survey .
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Robert E. Kriger Publ. Co..
Gaya MLA
SURVICE, U.S., DEPARTMENT, OF, AGRICULTURE;, SOIL, CONSERVATION.
"Soil taxonomy: A basic of soil classification for making and interpreting soil survey".
:
Robert E. Kriger Publ. Co.,
1988.
Buku.