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ISBN-13: 9783034870320, 978-3034870320. The text presented here is an extended english version of a report by the authors which appeared in April 1983 at the Institute of Cosmical Research of the Academy of Sciences of the GDR in German.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.