Regarding Sourdough Sam, the Last Fan Standing At Levi's
San Francisco 49ers - Wikipedia
San Francisco 49ers mascot Sourdough Sam is man of mystery.
Russell Wilson added the San Francisco 49ers mascot to the weekly scouting report to see if anyone would catch it, only DK Metcalf did, This is the Loop
Ranking the NFL's Mascots - Sports Illustrated
Sourdough Sam Official Mascot of the San Francisco 49ers
How much do NFL mascots make? Exploring contract stipulations for match-day stars
San Francisco 49ers Facts for Kids