https://www.imdb.com/title/tt0070992/ (IMDb)
https://www.biography.com/news/happy-days-cast-where-are-they-now (biography.com)
https://en.wikipedia.org/wiki/Happy_Days (Wikipedia)
https://vignette.wikia.nocookie.net/happydays/images/9/94/RichieCunningham.png/revision/latest?cb=20150227051828 (happydays.fandom.com)
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https://commons.wikimedia.org/wiki/File:Ron_Howard_2011_Shankbone.JPG (Wikimedia)-Attribution: David Shankbone [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0)]
https://en.wikipedia.org/wiki/Fonzie (Wikipedia)
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https://en.wikipedia.org/wiki/Potsie_Weber (Wikipedia)
https://www.facebook.com/photo.php?fbid=10201414843669514&set=ecnf.1127402948&type=3&theater (Anson Williams Facebook)
https://commons.wikimedia.org/wiki/File:MarionRossSept2011.jpg (Wikimedia)-Attribution: Angela George [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]
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https://www.biography.com/people/tom-bosley-13228(biography.com)
https://en.wikipedia.org/wiki/Joanie_Cunningham (Wikipedia)
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