Unknown Small Stamp Label. Help Identify!

Can anybody please help to identify these small stamps or labels. Country, purpose, etc. Any information would helpful.

Hello ajbbarbados

It seems that there are all from Austria.

The first row are from ÖMV (Österreichische Mineralölverwaltung => Austrian Mineral Oil Administration; today OMV).
Second row
first one: from Mietervereinigung Österreich => Tenants' Association Austria
the fourth one: from Österreichischer Gewerkschaftsbund => Austrian Federation of Trade Unions

It seems that they are a kind of confirmation that the membership fee was paid.

Please make a few larger scans of the remaining. Maybe then I'm able to identify the issuing agencies/companies/organisations.

Best regards from Switzerland

André

Unfortunately, this is the only picture I have. Its a picture I found online, and I thought I'd submit it to get them identified. I am really into unique stamps and labels like this, "back of the book" stuff (or sometimes not even in the book), so I wanted to get them identified to see if I could find some for sale somewhere.