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|---|---|---|
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| 0000919574-18-007801-index.html | 2018-11-29 17:32:01 | |
| 0000919574-18-007801.txt | 2018-11-29 17:32:01 | |
 0000919574-18-007801-xbrl.zip | 100891 | 2018-11-29 17:32:01 |
| d8106411_6-k.htm | 537179 | 2018-11-29 17:32:01 |
| FilingSummary.xml | 20457 | 2018-11-29 17:32:01 |
| Financial_Report.xlsx | 43681 | 2018-11-29 17:32:01 |
| nat-20180930.xml | 640736 | 2018-11-29 17:32:01 |
| nat-20180930.xsd | 31704 | 2018-11-29 17:32:01 |
| nat-20180930_cal.xml | 50736 | 2018-11-29 17:32:01 |
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| report.css | 2767 | 2018-11-29 17:32:01 |
| Show.js | 1085 | 2018-11-29 17:32:01 |