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| btu-20230930.xsd | 72789 | 2023-11-03 06:15:04 |
| btu-20230930_cal.xml | 79363 | 2023-11-03 06:15:04 |
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| btu-20230930_htm.xml | 1662549 | 2023-11-03 06:15:04 |
| btu-20230930_lab.xml | 852430 | 2023-11-03 06:15:04 |
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| btu_20230930xex311.htm | 10720 | 2023-11-03 06:15:04 |
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