buildingsmart sources not found
http://www.buildingsmart-tech.org/ifc/IFC4/Add1/html/ gives a 404 error.
I suppose that all the occurrences need to be replaced by https://standards.buildingsmart.org/IFC/RELEASE/IFC4_1/FINAL/HTML/
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http://www.buildingsmart-tech.org/ifc/IFC4/Add1/html/ gives a 404 error.
I suppose that all the occurrences need to be replaced by https://standards.buildingsmart.org/IFC/RELEASE/IFC4_1/FINAL/HTML/