UNESCO text Paris Unesco 1968 eng 200 p. : ill. ; 24 cm. Unesco SPACES COMMUNICATIONS 621.39 621.39 UNE c 220410 20220410092758 INLIS000000000031385 Converted from MARCXML to MODS version 3.5 using MARC21slim2MODS3-5.xsl (Revision 1.106 2014/12/19)