I think the copyright notice at the bottom is just website boilerplate. it's also on the main Stanford library website. The about page says "For commercial use, contact: [email protected]", so it is the Bibliothèque nationale de France that is claiming copyright. IANAL, but I think you'd be pretty safe using those images on servers hosted in the USA because then you'd be under the jurisdiction of U.S copyright law, but things can get messy as in this case where a British Museum threatened to take the Wikimedia Foundation to UK court: https://en.wikipedia.org/wiki/National_Portrait_Gallery_and_....