Caracterizacao qualitativa de substancias humicas de diferentes solos do nordeste paraense
[Qualitative characterization of humic substances of different soils in the norheast of Para] [Researches about soil use and soil conservation at the aestern Amazonia. Final report of the accord EMBRAPA-CPATU-GTZ]
- Documentos - Centro de Pesquisa Agropecuaria do Tropico Umido (Brazil) no. 40 ISSN 0101-2835 .
Pesquisas sobre utilizacao e conservacao do solo na Amazonia oriental. Relatorio final do convenio EMBRAPA-CPATU-GTZ Belem, PA (Brasil): 1986. p. 137-145 (BR8801815-AMS)