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| btu-20240331.htm | 1490174 | 2024-05-09 06:11:05 |
| btu-20240331.xsd | 69232 | 2024-05-09 06:11:05 |
| btu-20240331_cal.xml | 82047 | 2024-05-09 06:11:05 |
| btu-20240331_def.xml | 382362 | 2024-05-09 06:11:05 |
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| btu-20240331_htm.xml | 1070235 | 2024-05-09 06:11:05 |
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