Emmens, C. W. Principles of biological assay / C. W. Emmens. With a foreword by Percival Hartley. - London : Chapman & Hall , 1948. - xv, 206 p. : diagrs. ; 23 cm. LCCN: 49-006911 Subjects--Topical Terms: Biological assay.-------- Dewey Class. No.: 570.0031 EMM