id	keyword
american_scientific_journal-3976	draught
american_scientific_journal-3976	tillage
american_scientific_journal-3976	tractor
american_scientific_journal-3976	cut
american_scientific_journal-3976	field
american_scientific_journal-3976	soil
american_scientific_journal-3976	implements
american_scientific_journal-3976	nsct
american_scientific_journal-3976	trf
american_scientific_journal-3976	animal
american_scientific_journal-3976	namibia
american_scientific_journal-3976	research
american_scientific_journal-3976	engineering
american_scientific_journal-3976	journal
american_scientific_journal-3976	depth
american_scientific_journal-3976	tdh
american_scientific_journal-3976	arf