Guenther, Ernest Essential oils - New York: D Van Nostrand Company, Inc., 1949 Vol.2 (The constituents of essential oils); xiii, 852p.Vol. 4 (Individual essential oils of the plant...); xiv, 752p.Vol. 6(Individual essential oils of the plant families); xvi, 481p. Universal Decimal Class. No.: 668.5 / H9