@article{Joyal:AM:1981,
    Abstract = {This paper presents a combinatorial theory of formal power series. The combinatorial interpretation of formal power series is based on the concept of species of structures. A categorical approach is used to formulate it. A new proof of Cayley's formula for the number of labelled trees is given as well as a new combinatorial proof (due to G. Labelle) of Lagrange's inversion formula. Polya's enumeration theory of isomorphism classes of structures is entirely renewed. Recursive methods for computing cycle index polynomials are described. A combinatorial version of the implicit function theorem is stated and proved. The paper ends with general considerations on the use of coalgebras in combinatorics.},
    Author = {Joyal, Andr{\'e}},
    File = {Une théorie combinatoire des séries formelles - 1-s2.0-0001870881900529-main - a.pdf},
    ISSN = {0001-8708},
    Journal = {Advances in Mathematics},
    Number = {1},
    Pages = {1--82},
    Title = {Une th{\'e}orie combinatoire des s{\'e}ries formelles},
    URL = {https://www.sciencedirect.com/science/article/pii/0001870881900529},
    Volume = {42},
    Year = {1981},
    bdsk-url-1 = {https://www.sciencedirect.com/science/article/pii/0001870881900529},
    bdsk-url-2 = {https://doi.org/10.1016/0001-8708(81)90052-9},
    date-added = {2023-02-20 12:04:39 +0100},
    date-modified = {2023-04-26 07:54:10 +0200},
    doi = {10.1016/0001-8708(81)90052-9}
}

@article{Joyal:AM:1981, Abstract = {This paper presents a combinatorial theory of formal power series. The combinatorial interpretation of formal power series is based on the concept of species of structures. A categorical approach is used to formulate it. A new proof of Cayley's formula for the number of labelled trees is given as well as a new combinatorial proof (due to G. Labelle) of Lagrange's inversion formula. Polya's enumeration theory of isomorphism classes of structures is entirely renewed. Recursive methods for computing cycle index polynomials are described. A combinatorial version of the implicit function theorem is stated and proved. The paper ends with general considerations on the use of coalgebras in combinatorics.}, Author = {Joyal, Andr{\'e}}, File = {Une théorie combinatoire des séries formelles - 1-s2.0-0001870881900529-main - a.pdf}, ISSN = {0001-8708}, Journal = {Advances in Mathematics}, Number = {1}, Pages = {1--82}, Title = {Une th{\'e}orie combinatoire des s{\'e}ries formelles}, URL = {https://www.sciencedirect.com/science/article/pii/0001870881900529}, Volume = {42}, Year = {1981}, bdsk-url-1 = {https://www.sciencedirect.com/science/article/pii/0001870881900529}, bdsk-url-2 = {https://doi.org/10.1016/0001-8708(81)90052-9}, date-added = {2023-02-20 12:04:39 +0100}, date-modified = {2023-04-26 07:54:10 +0200}, doi = {10.1016/0001-8708(81)90052-9} }