00329nam a2200133Ia 4500008004100000082001600041100001500057245001400072260003500086300000800121650003400129650001800163653001400181170901s1980    xx            000 0 und d  a526.9bA25S  aAgor, S.S. 0aSurveying  aDelhibKhanna Publishersc1980  a864  aAstronomy and allied sciences  aPure Sciences  aSurveying