Sources

Every post ends with its own list of sources. This page explains where they come from and how to check them.

Where the evidence comes from

• Primary sources first: the manuscript, the experiment, the original paper, the historical document.
• Peer-reviewed research and books by specialists for interpretation.
• News and popular articles only for dates and events, never as the main evidence for a claim.

Libraries and archives we use

• The Metropolitan Museum of Art (Open Access, CC0)
• Rijksmuseum (public-domain collection)
• Beinecke Rare Book & Manuscript Library, Yale University
• Library of Congress
• NASA image and video library
• Internet Archive, including the Prelinger film archive

How images are licensed

Known, debated, speculation

Corrections

If something here is wrong, please write (the address is on the About page). Corrections are added to the top of the post with the date, and the video’s pinned comment is updated.