00514nam a2200157Ia 4500008004100000020001400041022001000055040001300065082001700078100001200095245007900107260004800186300003500234500006500269650002200334191130s2001##################000#0#eng##  a521791359  a68867  aACLcACL  a523.1135 KWO  aKwok, S  aCosmic butterflies : the colorful mysteries of planetary nebulaecSun Kwok  aCambridgebCambridge University Pressc2001  aix, 179 p. : col. ill. ; 27 cm  aIncludes bibliographical references (p. [169]-170) and index  aPlanetary nebulae