id	keyword
gssr-408	energy
gssr-408	emissions
gssr-408	tourism
gssr-408	raihan
gssr-408	growth
gssr-408	singapore
gssr-408	co2
gssr-408	co2 emissions
gssr-408	carbon
gssr-408	research
gssr-408	use
gssr-408	et al
gssr-408	study
gssr-408	data