TY - BOOK AU - Freeman,Roger L. TI - Practical data communications SN - 0471310212 (cloth : alk. paper) AV - TK5105 .F87 1995 U1 - 004.6 20 PY - 1995/// CY - New York PB - Wiley KW - Data transmission systems N1 - "A Wiley-Interscience publication."; Includes bibliographical references and index ER -