AGRIS: International Information Systems for the Agricultural Sciences and Technology
Useful database with literature on agricultural technology from 150 institutions in over 100 countries. Over 2.8 million citations from 1975 to present, many linking to the full text. Around 80% of the citations are from scientific journals, however, one of the strengths of AGRIS is the ability to find grey literature (unpublished literature you can't find elsewhere.)
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