TY  - BOOK
AU  - Jacobs, Hyde S.
TI  - Soils laboratory excercise source book
U1  - 631.4072 
PY  - 1971///
CY  - Madison, Wis.,
PB  - American Society of Agronomy
KW  - Suelos
KW  - Manuales de laboratorio
ER  -