text Demak Media Ilmu 1992 ind 108 hlm ilus 21 cm Francis, D.Yury Bibliografi : hlm. 108 Sistem interkomunikasi 621.381 20090227024301.0 YOGYA-02090000028995 Converted from MARCXML to MODS version 3.5 using MARC21slim2MODS3-5.xsl (Revision 1.106 2014/12/19)