Set of 8 French bills of exchange from 1950s with tax stamps and rubber-stamps.
Note that several bills of exchange have a hole in the lower left corner: these bills of exchange had to be stapled to the corresponding bills and had to be detached more or less cleanly once the customer had paid the expected amount.
The last photo shows the back of the bills of exchange.
These bills of exchange are financial instruments for loans between companies. Before the massive arrival of computers, these exchanges were carried out by hand as shown by these documents.