In 1891 Julius Petersen published a paper that contained his now famous theorem: any bridgeless cubic graph has a 1-factor. These days Petersen's theorem is always proven indirectly using major results such as Hall's theorem from 1935 and Tutte's theorem on 1-factors from 1947. We discuss a number of attempts that have been made over the years, including Petersen's as well as our own, at a direct proof of this theorem.
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