Sources

Where the facts come from

Yestermark is built on top of open data and freely licensed reference works. This page is the full attribution chain.

Textual sources

• Wikipedia (CC BY-SA 4.0) — date pages, year pages, decade pages, biographical ledes. Each page links to the specific source article in its footer.
• Wikidata (CC0) — structured biographical data: birth and death dates and places, occupations, country.
• Public Billboard year-end singles charts (via Wikipedia) — #1-song-of-the-year highlights.
• MusicBrainz (CC0) — supplementary music metadata where applicable.
• OMDb (free tier, custom permissive license) — film highlights for year pages.

Images

Every image on Yestermark is sourced from Wikimedia Commons under one of the following licenses: CC BY, CC BY-SA, CC0, or Public Domain. Each image's caption lists the photographer or author and the license. Any image whose license cannot be confirmed is excluded by the build pipeline; it never reaches a published page.

How Yestermark text is itself licensed

The original editorial text on Yestermark — ledes, framings, contextual paragraphs — is licensed under CC BY-SA 4.0. The brand name, the visual design, the source code, and the OG card templates are proprietary and not part of the CC license.

Reusing Yestermark text

If you'd like to reuse Yestermark editorial text under CC BY-SA, attribute as:

"Source: Yestermark (yestermark.com), CC BY-SA 4.0."

Linking to the specific page you drew from is preferred.

Corrections

Spot an error? Email hello@yestermark.com with the URL. I aim to respond within seven days.