Derfler, Frank J. <br/><br/>
TRS-80 data communication systems / 
Frank J. Derfler, Jr. 
 - Englewood Cliffs, N.J. :  Prentice-Hall,  1982. 
 - xi, 159 p. :  ill. ;  24 cm. 
<br/><br/> 'A Spectrum book.' 
<br/><br/>Includes index. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Data transmission systems.<br/>TRS--80 (Computer).