Symptoms of virus diseases in plants / by L. BOS Bos, L., 1928- Virus diseases of plants. SB736 .B63 1971 581.2 BOS "With indexes of names of symptoms in English, Dutch, German, French, Italian, and Spanish." Includes bibliographical references and index. Wageningen : Research Institute for Plant Protection, c 1978 c 1978 1971 Text 208 p. : eng