Native file for diagrams

What’s the native application that created these types of diagrams? Are the native files still around? Are they on some git repo somewhere?

I created most of those pictures that form part of the IFC specifications (at least until IFC4.1). Most were done in either plain autocad (like those) or visio. git repos were pretty much unknown at that time (those figures where added in IFC2x back in 1999 - if I recall well).

Thanks @TLiebich. Do you have access to these native files somewhere? If so, can you push them to a BS repo somewhere? I think they could be the basis of additional or refined/modified diagrams in the future.