@book{27727,
	author = {Krevelen, D. W. van and Schuyer, J.},
	title = {Coal science;},
	publisher = {Elsevier Pub. Co.,},
	year = {1957.},
	address = {Amsterdam,},
	note = {Rev. ed. published in 1961 under title: Coal: typology, chemistry, physics, constitution.}
}