Forest resources of the world / Raphael Zon and William N. Sparhawk ... with a foreword by Gifford Pinchot; prepared under the authority of the Secretary of Agriculture of the United States and in coöperation with the National Research Council ...[v0l. 1.] Zon, Raphael. 1874-1956. Sparhawk, William N. (William Norwood), 1888- joint author. National Research Council (U.S.) Forests and forestry. SD131 .Z75 1st ed. 634.92 ZOF Contains "References". New York : McGraw-Hill Book Co., c1923. c1923. 1923 Text xiv, p. : eng