%0 Generic %C [S.l.] : %D 1940. %I United States. Army. Chemical Warfare Service, %T FM 21-40 Defense Against Chemical Attack 1940 %U http://SK8ES4MC2L.search.serialssolutions.com/?sid=sersol&SS_jc=TC_027677239&title=FM%2021-40%20Defense%20Against%20Chemical%20Attack%201940