All articles are copyrighted by the publisher of the article.
They can only be downloaded for personal use. Any commercial use
or large-scale downloading is prohibited. Please see the Conditions of Use for more details.
We would like to acknowledge the many people and
organizations that have helped with this project by donating extra
volumes and by giving the ADS permission to scan their copyrighted
To access scanned proceedings please use the Proceedings Query Page.
To access scanned observatory/society publications please use the Observatories Query Page.