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| 0001564590-21-024459.txt | 2021-05-06 06:25:59 | |
 0001564590-21-024459-xbrl.zip | 177454 | 2021-05-06 06:25:59 |
| bv-10q_20210331.htm | 2848420 | 2021-05-06 06:25:59 |
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| bv-20210331_lab.xml | 355907 | 2021-05-06 06:25:59 |
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| FilingSummary.xml | 36482 | 2021-05-06 06:25:59 |
| Financial_Report.xlsx | 78734 | 2021-05-06 06:25:59 |
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