na INLIS000000000050027 eng 0010-0617008919 McGraw-Hill encyclopedia of Science and technology. Volume 6 GAB-HYS New York: McGraw-Hill Book Company, 1971 ..vol. 28 cm. 070797986 503 McG m 1 503 SCIENCE AND TECHNOLOGY-ENCYCLOPEDIAS 058786212 058786212 058786212 058786212