LaTeX realhats package—\hat{a} put real hats (dunce cap, Santa hat, top hat, cowboy hat, etc.) on symbols instead of â. https://ctan.org/pkg/realhats pic.twitter.com/eJabFM8dB6
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Picture of Lev Pontryagin wearing a hat: http://www.matematicaeducativa.com/foro/viewtopic.php?f=6&t=969&sid=eea7f0ab2d9994a3f0043c3661fab9b1 …
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