Cai, Jun Liang et Liu, Yan Pei, The Enumeration of General Rooted Planar Maps, Acta mathematica Sinica. English series (Print) , 21(1), 2004, pp. 215-224
This paper provides some functional equations satisfied by the generating functions for enumerating general rooted planar maps with up to three parameters. Furthermore, the generating functions can be obtained explicitly by employing the Lagrangian inversion. This is also an answer to an open problem in 1989.