Comets :  readings from Scientific American / 
compiled by John C. Brandt 
 - San Francisco :  W.H. Freeman,  1981 
 - xxxi, 92 p. :  ill. (some col.) ;  29 cm 
<br/><br/>Includes index Bibliography: p.  89 -90 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Comets