Counting rooted trees: the universal law t ( n ) ∼ C ρ - n n - 3 / 2 . Bell, Jason P.; Burris, Stanley N.; Yeats, Karen A. — 2006 The Electronic Journal of Combinatorics [electronic only]
Characteristic points of recursive systems. Bell, Jason P.; Burris, Stanley N.; Yeats, Karen A. — 2010 The Electronic Journal of Combinatorics [electronic only]