http://ipl.si.umich.edu/div/subject/browse/hea14.30.00/ has been crawled 23 times going all the way back to December 31, 2003.

A crawl can be a duplicate of the last one. It happens about 25% of the time across 420,000,000 websites. FAQ
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February 1, 2006

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February 12, 2006

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April 24, 2006

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June 12, 2006

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August 3, 2006

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August 7, 2006

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August 8, 2006

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August 30, 2006

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September 4, 2006

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September 7, 2006

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October 23, 2006

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Note

This calendar view maps the number of times http://ipl.si.umich.edu/div/subject/browse/hea14.30.00/ was crawled by the Wayback Machine, not how many times the site was actually updated. More info in the FAQ.