1. Several proofs of labeled 2-dimensional trees;Beineke,1969
2. The number of labeled k-dimensional trees;Beineke;J. Combin. Theory,1969
3. On q-trees;Chao;J. Graph Theory,1986
4. A general bijective algorithm for trees;Chen,1990
5. A bijective proof for the number of labeled q-trees;Egecioglu;ARS Combinatoria,1988