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| 0001564590-22-003010-index.html | 2022-01-28 16:15:19 | |
| 0001564590-22-003010.txt | 2022-01-28 16:15:19 | |
 0001564590-22-003010-xbrl.zip | 237401 | 2022-01-28 16:15:19 |
| extr-10q_20211231.htm | 3580541 | 2022-01-28 16:15:19 |
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| Financial_Report.xlsx | 109546 | 2022-01-28 16:15:19 |
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| report.css | 2767 | 2022-01-28 16:15:19 |
| Show.js | 1085 | 2022-01-28 16:15:19 |