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| 0001477932-19-003478-index.html | 2019-06-11 15:57:28 | |
| 0001477932-19-003478.txt | 2019-06-11 15:57:28 | |
 0001477932-19-003478-xbrl.zip | 154064 | 2019-06-11 15:57:28 |
| bvtk-20181231.xml | 1539285 | 2019-06-11 15:57:28 |
| bvtk-20181231.xsd | 93900 | 2019-06-11 15:57:28 |
| bvtk-20181231_cal.xml | 54452 | 2019-06-11 15:57:28 |
| bvtk-20181231_def.xml | 279316 | 2019-06-11 15:57:28 |
| bvtk-20181231_lab.xml | 336175 | 2019-06-11 15:57:28 |
| bvtk-20181231_pre.xml | 362278 | 2019-06-11 15:57:28 |
| bvtk_10k.htm | 722382 | 2019-06-11 15:57:28 |
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| bvtk_ex311.htm | 7239 | 2019-06-11 15:57:28 |
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| bvtk_ex321.htm | 2439 | 2019-06-11 15:57:28 |
| bvtk_ex322.htm | 2513 | 2019-06-11 15:57:28 |
| FilingSummary.xml | 37092 | 2019-06-11 15:57:28 |
| Financial_Report.xlsx | 91228 | 2019-06-11 15:57:28 |
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| report.css | 2767 | 2019-06-11 15:57:28 |
| Show.js | 1085 | 2019-06-11 15:57:28 |