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| 0000015847-26-000020-index.html | 2026-07-07 19:40:33 | |
| 0000015847-26-000020.txt | 2026-07-07 19:40:33 | |
 0000015847-26-000020-xbrl.zip | 264045 | 2026-07-07 19:40:33 |
| buks-20260430.htm | 1380633 | 2026-07-07 19:40:33 |
| buks-20260430.xsd | 60134 | 2026-07-07 19:40:33 |
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| report.css | 2767 | 2026-07-07 19:40:33 |
| Show.js | 1085 | 2026-07-07 19:40:33 |