Overview this study document includes considering the following databases: eLibrary, ProQuest, EBSCO, ERIC, UMI Dissertation Abstracts database, LINDA, data research in Vietnam such as: library of the University of Economics, HO CHI MINH CITY. HCM Vietnam, Vietnam Forestry University Library, Dongnai province statistics Almanac, figures of the World Wide Web, and from the reference document of the publication the magazine related to the agricultural economy and the factors affecting the yield of black pepper.
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