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| 0001437749-20-015329-index.html | 2020-07-17 11:44:15 | |
| 0001437749-20-015329.txt | 2020-07-17 11:44:15 | |
 0001437749-20-015329-xbrl.zip | 135407 | 2020-07-17 11:44:15 |
| buks-20200430.xml | 1045216 | 2020-07-17 11:44:15 |
| buks-20200430.xsd | 62087 | 2020-07-17 11:44:15 |
| buks-20200430_cal.xml | 63177 | 2020-07-17 11:44:15 |
| buks-20200430_def.xml | 391985 | 2020-07-17 11:44:15 |
| buks-20200430_lab.xml | 345066 | 2020-07-17 11:44:15 |
| buks-20200430_pre.xml | 425119 | 2020-07-17 11:44:15 |
| buks20200430_10k.htm | 1247709 | 2020-07-17 11:44:15 |
| ex_180678.htm | 5625 | 2020-07-17 11:44:15 |
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| FilingSummary.xml | 38116 | 2020-07-17 11:44:15 |
| Financial_Report.xlsx | 72942 | 2020-07-17 11:44:15 |
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| report.css | 2767 | 2020-07-17 11:44:15 |
| Show.js | 1085 | 2020-07-17 11:44:15 |