The target resource for this PURL can no longer be traced. The following is a list of the targets this PURL was previously assigned to.
| Timestamp | Target URL | Note |
|---|---|---|
| 10/14/10 22:07:26 | http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19900003697_1990003697.pdf | |
| 09/21/20 14:37:20 | https://ntrs.nasa.gov/citations/1990003697 | |
| 09/22/21 13:53:36 | https://purl.fdlp.gov/history/GPO/LPS61173 | Withdrawn from the Federal Depository Library Program, 8/2021 |