Archimedes by Domenico-Fetti (1620). Public domain.
The Moneychanger and his Wife. by Marinus van Reymerswaele (c.1490–c.1546). Public domain.
Landscape with Cottage and Haybam by Rembrandt Harmenszoon van Rijn (1606 - 1669). Public domain.
Le Roi Boit (The King Drinks) by Jacob Jordaens (1593-1678). Public domain.
Tromso Cityscape by Vichaya Kiatying-Angsulee. Paid license.
Cottage by Joe Dyndale. CC BY-ND 2.0.
Alamo Square, San Francisco by porbital. Paid license.
Inside a Post Office Savings Bank deposit book by UK General Post Office. Public domain.