TY  - JOUR 
T1  - Chemical nature of soil humified fractions and their bioactivity
JO  - Pesquisa Agropecuária Brasileira
A1  - Canellas, Luciano Pasqualoto
A1  - Façanha, Arnoldo Rocha
SN  - 0100-204X
UL  - 10.1590/S0100-204X2004000300005
VL  - 39 
Y1  - 2004
PB  - Brazil 
ER  -