id	keyword
dem-2904	oil
dem-2904	cycle
dem-2904	price
dem-2904	crude
dem-2904	regime
dem-2904	business
dem-2904	business cycle
dem-2904	price cycle
dem-2904	models
dem-2904	oil price
dem-2904	switching
dem-2904	markov
dem-2904	poland
dem-2904	table
dem-2904	countries