_:vb7271020	<http://purl.org/dc/terms/bibliographicCitation>	"1918 February, Guy Elliott Mitchell, \u201CBillions of Barrels of Oil Locked up in Rocks\u201D, in Gilbert H[ovey] Grosvenor, editor, National Geographic, volume XXXIII, number 2, Washington, D.C.: National Geographic Society\u00A0[\u2026], \u2192ISSN, \u2192OCLC, page 205, column 2:"@en .
_:vb7271020	<http://www.w3.org/1999/02/22-rdf-syntax-ns#value>	"[H]ere in America there are mountains of oil rock which can be blasted and steam-shoveled and transported by gravity to great retorts which will turn out oil and fertilizer in limitless quantities."@en .